importance of closing volume

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Introduction, the lung volumes.

• MEASUREMENT OF THE LUNG VOLUMES
• ANATOMIC DEAD SPACE AND ALVEOLAR VENTILATION
• MEASUREMENT OF ALVEOLAR VENTILATION
• ALVEOLAR VENTILATION AND ALVEOLAR OXYGEN AND CARBON DIOXIDE LEVELS
• REGIONAL DISTRIBUTION OF ALVEOLAR VENTILATION
• THE CLOSING VOLUME
• THE EFFECTS OF AGING
• KEY CONCEPTS
• CLINICAL PROBLEMS
• CLINICAL CORRELATION
• SUGGESTED READINGS
• Full Chapter
• Supplementary Content

The reader understands the ventilation of the alveoli .

Defines alveolar ventilation .

Defines the standard lung volumes and understands their measurement .

Predicts the effects of alterations in lung and chest wall mechanics, due to normal or pathologic processes, on the lung volumes .

Defines anatomic dead space and relates the anatomic dead space and the tidal volume to alveolar ventilation .

Understands the measurement of the anatomic dead space and the determination of alveolar ventilation .

Defines physiologic and alveolar dead space and understands their determination .

Predicts the effects of alterations of alveolar ventilation on alveolar carbon dioxide and oxygen levels .

Describes the regional differences in alveolar ventilation found in the normal lung and explains these differences .

Predicts the effects of changes in lung volume, aging, and disease processes on the regional distribution of alveolar ventilation .

Defines the closing volume and explains how it can be demonstrated .

Predicts the effects of changes in pulmonary mechanics on the closing volume .

Alveolar ventilation is the exchange of gas between the alveoli and the external environment. It is the process by which oxygen is brought into the lungs from the atmosphere and by which the carbon dioxide carried into the lungs in the mixed venous blood is expelled from the body. Although alveolar ventilation is usually defined as the volume of fresh air entering the alveoli per minute, a similar volume of alveolar air leaving the body per minute is implicit in this definition.

The volume of gas in the lungs at any instant depends on the mechanics of the lungs and chest wall and the activity of the muscles of inspiration and expiration. The lung volume under any specified set of conditions can be altered by pathologic and normal physiologic processes. Standardization of the conditions under which lung volumes are measured allows comparisons to be made among subjects or patients. The size of a person’s lungs depends on his or her height and weight or body surface area, as well as on his or her age and sex. Therefore, the lung volumes for a patient are usually compared with data in a table of “predicted” lung volumes matched to age, sex, and body size. The lung volumes are normally expressed at the Body Temperature and ambient Pressure and Saturated with water vapor (BTPS). Determination of accurate lung volumes and capacities requires a conscious, cooperative subject who understands the instructions.

The Standard Lung Volumes and Capacities

There are four standard lung volumes (which are not subdivided) and four standard lung capacities, which consist of two or more standard lung volumes in combination ( Figure 3–1 ).

The standard lung volumes and capacities. Typical values for a 70-kg adult (standing or sitting upright) are shown.

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Forty years of closing volume

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G. B. Drummond, J. Milic-Emili, Forty years of closing volume, BJA: British Journal of Anaesthesia , Volume 99, Issue 6, December 2007, Pages 772–774, https://doi.org/10.1093/bja/aem330

The fundamental features of ‘airway closure’ were described in a landmark paper by Dollfuss and colleagues, 1 published 40 years ago in 1967. This paper showed a tracing of exhaled gas composition, related to lung volume. The subject first exhaled to residual volume and then inhaled a small quantity of an insoluble gas, followed by normal air, filling the lungs to total lung capacity (TLC). In the following slow expiration, the expected alveolar plateau showed an inflexion, with an increase in the tracer gas concentration as lung volume approached the end of expiration, that is, residual volume. The interpretation was that the lung emptied unevenly. The change in tracer gas concentration indicated that the final part of the exhaled gas came from parts of the lung that had received more of the initial inspirate: the principle of ‘first in, last out’ (Fig.  1 ). Indications that a decrease in lung volume would reduce ventilation of portions of the lung, and could in some circumstances cause hypoxaemia, had already been reported: in dogs with the thorax open 2 3 and in man during active expiration. 4 At first, the exact mechanism of the phenomenon of airway closure was unclear. A series of elegant experiments slowly unravelled the relative contributions of transpulmonary pressure and airway collapsibility, and the relationship between changes in airway patency and lung mechanics. 5–7 Better methods, with high resolution of lung images, have supported and extended the original concept. For example, inhaling a bolus of labelled particles that remain in the lung can provide an image of the patchy pattern of ventilation in asthma. 8

The proposed mechanism of the CV manoeuvre with a tracer gas. ( a ) The lung is at RV, and a bolus of tracer gas is inspired, which passes into lung regions served by airways that remain open. Lung regions with closed airway do not receive any tracer gas. ( b ) The tracer gas bolus is followed by unlabelled air. As this unlabelled air is inspired, it dilutes the tracer gas according to the regional ventilation pattern of the lung. Those regions that were closed have opened, and receive air. ( c ) TLC is reached. The alveoli that were open at RV contain tracer gas: the alveoli that were closed, and the airways, contain air only. ( d ) Expiration has started and airway gas containing no tracer is exhaled: this is dead space gas. ( e ) The ‘alveolar plateau’ contains slightly varying contributions from different lung regions (partly because of cardiac movement). The exhaled concentration represents this variation in contributions from different regions. ( f ) As airway closure starts, the lung regions that contain less or no tracer gas cease to contribute to expired gas. Consequently, the tracer gas concentration in the expired gas increases, as it now is only issuing from labelled lung regions. The lung volume at which airway closure starts is called closing capacity, and the difference between CC and RV is the CV.

In the following 40 yr, the concept of airway closure was applied in a number of important and disparate ways, as knowledge of lung biology advanced. At first, closing volume (CV) was considered useful to study lung disease caused by smoking or air pollution, as a marker of small airway damage which could not be detected by simple spirometry. For example, a large study of smokers found that although only 11% had abnormal spirometry, 44% of them had abnormal CVs. 9 Initial enthusiasm waned as it became clear that, although sensitive, the measure was poorly reproducible and not predictive, 10 perhaps partly because it was as much a marker of inflammation of the small airways as it was of structural damage,

Interest shifted, and a lot of research reported on the relationship between airway closure and impairment of gas exchange. A seminal study had already shown that posture affected lung efficiency in that recumbency increased the difference in nitrogen partial pressure between tissues and alveolar gas. 11 This observation was interpreted using knowledge of the behaviour of inert gases, new at the time, that laid the foundation for much of our understanding of gas exchange, the effects of matching between ventilation and perfusion, and many of the methods we now use. In lung units that are poorly ventilated, not only is the oxygen tension low, but the nitrogen tension is high. Blood leaving these units increases the arterial nitrogen tension and thus provides a clear, if indirect, sign that lung units with low ventilation/perfusion ratios must be present. Such conditions could occur if airway closure were to occur during tidal breathing, in other words when closing capacity was greater than functional residual capacity, as might occur in the supine position, in pregnancy, 12 obesity, 13 with ageing, 14 voluntary reduction of lung volume, 15 after abdominal surgery, 16 and in heart failure. 17 Later, the direct evidence of airway closure reinforced the initial deductions. Since oxygenation is impaired during anaesthesia, and studies had been published about that time showing how FRC was reduced by anaesthesia, the relationship between CV and impaired oxygenation during anaesthesia was also studied. 18 Applying positive end-expiratory pressure during anaesthesia to increase lung volume did indeed improve oxygenation, 19 20 but the effect was only seen in those with poor oxygenation, and was not very marked: an increase from 10.3 to 13.6 kPa by 15 cm H 2 O PEEP! 20

A third stage of interest in airway closure has now developed, along with the understanding of how the lung and airways may be damaged by the process of ventilation itself. When lung inflation starts from residual volume, the lung tissue that is inflating will not include those parts where airways are closed. At the start of inflation, the lung is functionally ‘smaller’, and the quantity of participating tissue progressively increases as the airways open. Thus, the mechanical properties change, and this may be seen as an inflexion, or change of slope, on the pressure–volume plot. 6 21 This can also be detected as a change in airway resistance 22 and as sounds in the airway. 23 The airway opening occurs in a stepwise manner, indicating a hierarchical pattern of airway opening. 24 The pressure–volume relationship of the respiratory system of anaesthetized patients shows how airways re-open over a large range of pressures, probably up to 20 cm H 2 O. 25 The successive re-opening of these airways, even in normal lungs ventilated at low lung volumes, leads to damage, and can be prevented by maintaining the lung volume and a normal end-expiratory volume. 26 The lung damage is also made worse if the inflation rate of mechanical ventilation is increased. 27 A picture has emerged of another mechanism of ‘volutrauma’ where repeated opening and closing of the airways is a damaging mechanism, 28 interacting with other damaging mediators, 29 just as excessive tidal volumes were proposed as harmful, 30 and can cause poor outcome even after a few hours of anaesthesia. 31

During deflation, as the lung gets smaller, the number of airways contributing to the expired flow declines, and the flow is reduced. In patients with emphysema, who have increased CV and reduced lung recoil, expiratory flow limitation may be present. When this happens, incomplete expiration leads to lung hyperinflation and dyspnoea on exertion. 32 33 This flow limitation during expiration may be yet another mechanism of airway damage. 34 In animals, ventilation at low lung volumes causes disruption of the airway epithelium, disruption of alveolar attachments to the airways, and inflammation. The resistance of these airways increases, which is likely to make dynamic airway closure even more severe. 26 In many circumstances, changes in posture and variations in breathing pattern may ‘share out’ this damage in different parts of the lung. However, in the obese immobile patient receiving mechanical ventilation, flow limitation may occur in the same small airways for several hours, leading to damage. 35 Flow limitation is also evident in patients receiving intensive care. 36 One means of ‘sharing out’ the damage may be to vary the pattern of ventilation, which has been shown to prevent a progressive deterioration of lung function with standard ventilation. 37

The concept of airway closure over the last 40 yr has been a valuable idea that we have been able to apply respiratory measurements to explain disease and provide solutions to clinical problems, by combining experiment and clinical investigation with more recent ideas of inflammation without losing sight, or understanding, of mechanical reality!

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Volumes and Capacities

Explain the measurement of lung volumes and capacities, and factors that influence them

State the normal values of lung volumes and capacities

Define closing capacity and its clinical significance and measurement

The lung has four volumes and four (main) capacities:

• A volume is measured directly
• A capacity is a sum of volumes
• Normal is 7ml.kg -1 , or 500ml
• Normal is 45ml.kg -1 , or 2500ml
• Normal is 15ml.kg -1 , or 1500ml
• Normal is 15-20ml.kg -1 , or 1500ml
• Normal is 30ml.kg -1 or 3000ml
• FRC decreases 20% when supine, and a further 20% under general anaesthesia
• Normal is 4500ml
• Normal is 3000ml
• Normal is 6000ml

Functional Residual Capacity

The FRC has many important physiological functions:

Gas exchange The FRC allows blood in the pulmonary circulation to become oxygenated throughout the respiratory cycle (if there was no FRC , then at expiration the lungs would be empty and no oxygenation would occur).

Oxygen Reserve FRC is the only clinically modifiable oxygen store in the body, and allows continual oxygenation of blood during apneic periods.

• Below FRC , some alveoli collapse and the volume of lung available to receive the tidal volume decreases Re-expansion of collapsed alveoli requires more work than expanding open alveoli.
• Above FRC , some alveoli will become overdistended and their compliance will fall
• Airway resistance decreases as airway radius increases as lung volume increases
• Above FRC , compression of intra-alveolar vessels occurs and PVR increases
• Below FRC , extra-alveolar vessels collapse and PVR increases
• Maintain lung volume above closing capacity If closing capacity (see below) exceeds FRC , then shunt will occur.

Factors affecting FRC :

• Supine positioning Falls by ~20%.
• Anaesthesia Falls by ~20%.
• Raised intra-abdominal pressure
• Impaired lung and chest wall compliance
• Acute asthma
• Age May increase slightly.

Measurement of Lung Volumes and Capacities

• The patient exhales as fast as possible through the flow meter
• A flow-time curve is produced
• This curve can be integrated to find volume
• Any capacity which is a sum of these (IC, VC) can therefore be calculated
• Therefore FRC and TLC cannot be calculated
• Gas dilution
• Body plethysmography

Gas Dilution

• Conservation of Mass
• Helium has poor solubility and will not diffuse into circulation
• Only gas communicating gas can be measured - will underestimate FRC in gas-trapping
• Patient takes several breaths from a gas mixture containing a known concentration of helium (giving time for equilibration)

Body Plethysmography

• Patient is placed in a closed box, with a mouthpiece that exits the box
• When the patient inhales, the volume of gas in the box decreases (the patient takes up more space) and therefore the pressure increases

Closing Capacity

• Because dependent lung is compressed by gravity, dependent (typically basal) airways are of smaller calibre than non-dependent (typically apical) airways
• During expiration, these airways are compressed first Alveoli connected to these airways are isolated, and V/Q scatter or shunt occurs.
• FRC is decreased
• CC exceeds FRC in the supine patient at 44
• CC exceeds FRC in the erect patient at 66
• This is clinically relevant during preoxygenation , as it will limit the denitrogenation that can occur

Measurement of Closing Capacity

Closing capacity is measured using Fowler's Method, and is covered under Dead Space .

• Chambers D, Huang C, Matthews G. Basic Physiology for Anaesthetists. Cambridge University Press. 2015.

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Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC, Ortega R. Clinical anesthesia. 7th ed. Philadelphia: Lippincott Williams & Wilkins; 2013.

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Biggs, D.A. (2017). Spirometry. In: Raj, T. (eds) Data Interpretation in Anesthesia. Springer, Cham. https://doi.org/10.1007/978-3-319-55862-2_77

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Physiology, functional residual capacity.

Erin Hopkins ; Sandeep Sharma .

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Last Update: December 26, 2022 .

• Introduction

Functional residual capacity (FRC), is the volume remaining in the lungs after a normal, passive exhalation. In a normal individual, this is about 3L. The FRC also represents the point of the breathing cycle where the lung tissue elastic recoil and chest wall outward expansion are balanced and equal. Thus, the FRC is unique in that it is both a volume and related directly to two respiratory structures.

FRC is the total amount of air in a person’s lungs at the lowest point of their tidal volume (TV), where the tidal volume is the volume of air a person normally inspires and expires. The FRC is a lung capacity, consisting of the sum of two or more volumes. It also cannot be measured directly using spirometry and has to be calculated. This because FRC is a combination of the expiratory reserve volume (ERV) and the residual volume (RV). The residual volume is the amount of air remaining the lung after expelling as much air from the lungs as possible.  [1]  The residual volume can never be exhaled; thus, it cannot be measured using spirometry and is the air causing the alveoli to remain open. The expiratory reserve volume (ERV) is the reserve amount of air that can be exhaled forcefully, after passive exhalation. Therefore, the FRC can be represented as the equation: FRC= RV+ERV

FRC is also the point at which two forces are at equilibrium; the inner recoil forces of the lung due to the elastic tissue of the alveoli,  and the chest wall which wants to expand outwards. [2] [3] [4]

The FRC is important because it is related to several factors such as airway and vascular resistance, work of breathing, compliance, oxygen reserve, closing capacity, and V/Q mismatch.  

• Reduced lung volumes result in reduced FRC. Low lung volumes result in less alveolar tension pulling the lung airways open, and the airway narrowing results in increased airway resistance.
• Pulmonary vascular resistance is a combination of alveolar and extra-alveolar vessel resistances and is U-shaped. https://www.ncbi.nlm.nih.gov/books/NBK554380/ Thus, there are larger resistances at TLC and RV, and the lowest resistance is at the FRC volume.
• At FRC, the work to inflate the lungs is the lowest, as the inward and outward lung compliances are balanced.
• The compliance of the lung depends on the elastic recoil of the lung tissue. Decreases in this result in an increased FRC.
• The FRC results in an oxygen reserve, the residual air volume in the lungs allows for oxygen exchange. This oxygen reserve, and FRC, are important during the induction of anesthesia.
• A reduced FRC can result in shunts and atelectasis. This occurs when the FRC decreases below the closing capacity of the lung; the volume at which the respiratory bronchioles collapse.

 The FRC is affected by conditions that affect lung compliance; a combination of the inward elastic recoil of the lung, and outward expansion of the chest wall. These include diseases or conditions with changes in lung tissue compliance (emphysema, and interstitial lung diseases), decreased chest movements (kyphoscoliosis), or decreased thoracic volume (obesity, pregnancy). Other factors affecting FRC include acute changes in positions such as lying supine, age, height, and gender.

FRC is altered by the patients’ positioning, with it being greatest when upright and decreasing when supine or prone,  [5]  the latter resulting in airway closure of some lung regions. Even larger changes can be observed with patients in the Trendelenburg and head down positions.

  Age

As humans age, our pulmonary function also declines due to decreases in respiratory muscle mass, and tissue elasticity.  Loss of elasticity in connective tissue increases the work of breathing; similar to chronic obstructive pulmonary disease (COPD) (but to a lesser extent), the air becomes harder to expel and the lungs do not as readily return to normal size after inspiration. Thus the FRC increases slightly with age.

Height and Gender

A tall person had a larger lung volume and thus a greater FRC. Gender also affects FRC. Men tend to have a significantly larger lung volume even when compared to women of the same height and age. [6] This is due to structural differences between men and women. Women have s smaller ribcage, ribs that are angled or inclined differently than men, and a shorter diaphragm length.  [6]  However, due to the difference in the rib angle, women have a greater capacity to expand their lungs which is likely to aid physiological changes that occur during pregnancy.  [6]  

In pregnant women, spirometry remains within normal limits, however structural and volumes/capacities change significantly. The diaphragm relaxes due to hormonal changes), and the growing fetus begins to exert pressure on the thoracic cavity. This causes both the RV and ERV to decrease, which leads to a decreased FRC. Because of the lowered FRC and pressure on the thorax, a pregnant woman is more susceptible to atelectasis.  [7]

  Ascites and obesity

FRC also changes with ascites or obesity. These FRC decreases are due to increased pressure on the diaphragm, and a reduction of thoracic volume. This is one of the causes of shortness of breath.

Anesthetics alter FRC by affecting the tone or relaxation of the respiratory muscles. There is a debate as to the contribution of the rib cage and diaphragm to the decreased FRC.

• Related Testing

Lung volumes are followed to track a patient’s respiratory disease. While not routinely used in clinical practice, one way to measure residual volume and total lung capacity (TLC) is to measure a person’s FRC. 

FRC can be measured/calculated by using techniques such as the whole body plethysmograph method (based on Boyle’s Law), and the helium dilution method (based on the Law of Conservation of Mass).  [8]

• Clinical Significance

 In restrictive diseases, the TLC decreases, resulting in decreased FRC, and the lung tissues or chest wall expansion are limited or restricted.  One example of restriction due to chest wall issues is severe kyphosis or weakness of spinal bones. Kyphosis is described elsewhere.  [9]  Restrictive pathology can also be due to lung tissues, and one example is idiopathic pulmonary fibrosis. This disease is described elsewhere.  [10]

With obstructive diseases such as emphysema, the FRC is increased. With emphysema, the lungs become increasingly compliant, due to alveolar destruction. As the alveoli are destroyed, air is trapped in the lungs, and TLC is increased.  The increased volume and lung tissue compliance causes the chest wall to expand, hence, the typical barrel chest seen in those with emphysema.

While other lung values are more widely used clinically, functional residual capacity (FRC) contains utility both in understanding the respiratory cycle and in clinical practice. Since FRC is the equilibrium point for the forces of the chest wall and lung, it is an efficient starting point when learning about the chest wall/lung system. Both clinicians and researchers use methods to calculate FRC to obtain values that cannot be measured by standard spirometry. [11] [12] [13]

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Disclosure: Erin Hopkins declares no relevant financial relationships with ineligible companies.

Disclosure: Sandeep Sharma declares no relevant financial relationships with ineligible companies.

This book is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ), which permits others to distribute the work, provided that the article is not altered or used commercially. You are not required to obtain permission to distribute this article, provided that you credit the author and journal.

• Cite this Page Hopkins E, Sharma S. Physiology, Functional Residual Capacity. [Updated 2022 Dec 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

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• Review Intraalveolar bubbles and bubble films: II. Formation in vivo through adulthood. [Anat Rec. 1996] Review Intraalveolar bubbles and bubble films: II. Formation in vivo through adulthood. Scarpelli EM, Mautone AJ, DeFouw DO, Clutario BC. Anat Rec. 1996 Oct; 246(2):245-70.
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9 Sales KPIs Every Sales Team Should Be Tracking

More sales data isn't always better. You need a clear focus on metrics that matter. Here are 9 critical sales KPIs to drive confident decisions and grow revenue.

Jeffrey Steen

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Ever been overwhelmed by the sheer volume of sales data you’re tracking — and confused by the metrics that matter? You’re not the only one. Research firm  McKinsey  highlighted this as a troubling trend: Too much data and no focus has made it difficult for sales leaders to reach clear “aha” moments that drive confident decisions and sustainable growth.

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Key performance indicators (KPIs) in sales are the metrics used to measure how closely the performance of a sales team tracks to predetermined goals and how this performance impacts the business as a whole. This includes metrics like average leads generated per quarter and deal conversion rate.

Instead of different reps focusing on different metrics — or leaders eyeing a definition of success that sales reps aren’t thinking about — KPIs keep everyone aligned on the metrics that contribute to company growth. It’s important to note that KPIs themselves are not sales targets , but metrics that gauge activity with significant business impact. Sales leaders define target KPIs to ensure teams are tracking to specific revenue goals.

Here’s an example: Joy’s Toys, a toy manufacturer, is focused on growth but doesn’t have a clear target KPI for lead generation that incentivizes reps to keep their  pipelines full . Fast-forward a quarter or two and its revenue is “stop-and-go” with reps scrambling to find new opportunities after periods of focusing only on closing deals already in the pipeline. As a result, company growth stalls.

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Your sales KPIs have a close relationship with your sales and business goals. For example, if the overarching business goal is 1,200 sales in a year, the KPI might be 100 sales each month. (100 sales per month x 12 months = 1,200 sales)

Sales metrics are any quantifiable measure of sales performance. This could look like the number of activities completed by sales reps, the number of leads in the sales pipeline, or anything else sales-related that can be measured. The key difference is that your sales metrics don’t necessarily have to connect with these broader goals.

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Historically, sales KPIs have focused on things like new leads in the pipeline, number of  closed deals  per quarter, and individual quotas. These are still important, but they often hinge on unpredictable one-off sales. To ensure your company is generating long-term, predictable revenue and maximizing ROI, it’s important to track both foundational sales KPIs and those that gauge the lifetime value of customer and employee relationships.

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1. Annual contract value (ACV)

What it measures: The average sales amount of a customer contract over the course of a year.

Why it’s important:   ACV  helps sales reps and managers identify opportunities for upselling and  cross-selling  that increase customer contract value and, ultimately, company revenue. If upselling or cross-selling are not possible (due to product portfolio, pricing structures, etc.), a low ACV may indicate a need for new customers that can drive revenue growth.

How to calculate: (Total sales value of contracts in a year) / (number of contracts) = Average ACV

2. Customer lifetime value (CLV)

What it measures: The value of all purchases, including upsells, cross-sells, and renewals, that a customer makes over the course of their relationship with your company.

Why it’s important:   CLV  is a clear indicator of how successfully your team is building the kind of trusting, value-first, and loyal customer relationships that lead to upsells, cross-sells, and renewals, and, as a result, predictable revenue. If your CLV is on the lower end, then try going over the call transcripts from your best customers. Use AI to generate call summaries that identify what moved the deal forward, then use these same tactics in future deals.

How to calculate: (Average purchase value per year) x (average number of purchases per year for each customer) x (average customer lifespan in years) = Customer lifetime value

3. New leads in pipeline

What it measures: The number of new leads added to each rep’s pipeline during a single quarter.

Why it’s important: Based on your conversion rates (four deals closed for every seven leads, for example), you will likely need a specific number of leads to hit sales targets. If reps’ lead count falls below your target KPI, it can be a sign that you need to spend more time on prospecting . A popular way to engage with more prospects is to up your presence on LinkedIn. Follow potential prospects, interact with them by liking and commenting on their posts, and then send a connection request.

4. Average age of leads in pipeline

What it measures: How long leads remain in the pipeline without becoming a closed deal. Usually calculated per rep.

Why it’s important: Reps know a full pipeline is a healthy one — but only if leads are actively moving toward a sale. Stalled deals are a drain on rep time that could be spent moving more viable deals down the pipeline. If you see a trend in stale leads for a particular rep, consider examining their pipeline and remove leads unlikely to close. AI insights help to quickly identify the stallers in real time so you’re not spending hours scanning through your pipeline and analyzing the data.

How to calculate: (Total age of all active leads per reps) / (Number of active leads) = Average age of leads in pipeline

Reps fall in love with deals, even if they’re stagnant. When I think about pipeline aging, if it’s stale — it’s trouble. Larry Long, Jr.

5. Conversion rate

What it measures: Also known as win rate, this is the percentage of each rep’s leads that are converted to closed deals. Usually tracked by quarter, per rep.

Why it’s important: If a single rep’s conversion rate is higher than the target conversion rate, that rep may be using sales strategies or processes that are particularly effective and can be operationalized for the entire sales team. If lower, you might need to fine-tune or streamline sales tactics to increase conversions.  Call recording and analysis  tools, alongside regular one-on-one  coaching , can help.

How to calculate: (Number of deals closed during a quarter) / (number of leads in the pipeline) x 100 = Conversion rate

6. Rep retention

What it measures: Percentage of reps who remain in your organization a set period of time after hire. Typically measured yearly.

Why it’s important: A low rep retention rate can disrupt carefully nurtured customer relationships, which can result in lost upsells/cross-sells — or just lost customers. It can also mean more money spent onboarding reps hired to replace those who leave. When rep retention is high, customer relationships remain intact and team stability is maintained.

How to calculate: (Number of total reps at the end of the year – new reps hired during the year)/(total number of reps at the start of the year) x 100 = Rep retention

7. Average rep ramp time

What it measures: The amount of time it takes a rep to get from the first day on the job to first prospect outreach.

Why it’s important: A quicker ramp time indicates your  sales enablement platform  and training are effective, your tools and processes are intuitive, and you’re hiring qualified candidates.   This results in faster sales and more engaged reps. If you find ramp time is slow, consider revisiting onboarding programs and sharing AI transcripts of winning sales calls with new reps, changing your tools, or streamlining your processes.

How to calculate: (Total time in days it takes all new reps to get from day one to first prospect outreach) / (total number of new reps) = Average rep ramp time

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8. referrals.

What it measures: The number of referrals for new customers from existing customers secured by each rep during a given quarter.

Why it’s important: When your customers are over-the-moon happy with your products or services, they can serve as advocates, promoting you to prospects who otherwise may not be familiar with your brand. This makes it easier for reps to sell, leading to faster  sales cycles  and more closed deals.

9. Customer retention

What it measures: The percentage of customers who continue to buy and use your products/services. The inverse is churn rate — the percentage of customers who decide to stop buying or using your products/services.

Why it’s important: While new customers add to revenue, they also take  significant resources to secure . By watching customer retention and focusing on opportunities to upsell and cross-sell, you’re generating predictable revenue with a loyal customer base — and maximizing ROI. If you see customer retention slip, you may need to revisit rep engagement strategies to ensure your team is prioritizing existing customer relationships.

How to calculate: (Overall number of customers at the end of the year – net new customers acquired during the year) / (number of customers at the start of the year) x 100 = Customer retention

A CRM uses customer and sales performance data to gauge progress toward sales KPIs. To help with interpretation, most CRMs offer visualization tools or dashboards that can be customized with the KPIs most relevant to your business. The dashboard provides a clear picture of sales and company health so everyone from sales reps to leaders can make decisions that keep revenue flowing.

We’re in noisier, more competitive markets, and businesses are relying on new data sources to scale against competition. You can still build a seven-figure business with a phone and Excel, but if you want to do it better, you need the right technology. Alex Alleyne

To make sure everyone is in the loop, you need dashboards that provide high-level status updates to C-suite executives and more granular, deal-based dashboards for your reps. You don’t have to worry about updating dashboards manually — automation and  AI-powered CRMs  can pull data directly into customized dashboards to help you see progress toward KPIs without manual lift. Use these insights to improve performance, like tracking the fastest rep ramp times and checking in with those reps to see what worked that you could replicate.

Here are the dashboards we recommend for how to track sales KPIs:

For chief revenue officers (CROs) and sales leaders:

• Home “State of the Union” Dashboard: This provides an overview of top-level, year-to-date performance by target KPIs. It gives you the most important metrics for your business on one screen, including notable open and closed deals (usually the biggest accounts by value), top sales reps by quota attainment, and overall sales performance vs.  forecast .

For sales managers:

• Pipeline Dashboard: Get a snapshot of each rep’s pipeline with this dashboard, including average sales cycles, average deal amounts, and conversion rates. You’ll get clarity on the progression of deals in each pipeline and identify problem areas you need to address quickly.
• Team Activities Dashboard: See what your team’s doing to stay on top of active deals. Look at their total, completed, and overdue tasks and review each rep’s call and email logs. Dive deeper into conversations by looking at AI-generated call summaries. Use these summaries to identify customer sentiment and help move deals forward. Overall, this dashboard is key for monitoring rep engagement and  sales process  efficiency.

For sales operations (sales ops) teams:

• Performance Dashboard: Drill into closed deals by region, account, or product so you can see what’s contributing to high deal win rates or slowing conversions. Once you know the “why,” you can recommend strategy shifts for your team.
• Stage Analysis Dashboard: This dashboard shows how deals across all reps are moving through the stages of the sales process, revealing bottlenecks and at-risk opportunities. Trends and patterns identified with AI can reveal opportunities for process improvements.

For sales reps:

• Rep and Team Leaderboard Dashboards: This is an overview of individual rep and team performance data, including  sales quotas  attainment, leads in pipe, pipe generation, closed/won deals, average sales cycle time, and sales activities.

For more guidance, check out our article on key sales  KPI dashboards  that can help you hit or exceed your revenue targets.

Home in on the sales KPIs that matter to you

There’s no shortage of sales KPIs to track — but zeroing in on the right ones depends on what’s important to your business right now. First, identify overarching goals. For example, are you focused on driving growth or maximizing revenue with existing resources and investments?

Once you’re aligned on larger goals, you can select relevant sales KPIs to track and target metrics that will ensure you hit your broader business goals. Be sure to set up dashboards in a  CRM  accessible to all teams so you can see a clear view of progress toward the goals you’ve defined.

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VOL. 6 END OF VOLUME REPORT

Player insights and community feedback collected during the volume, need for speed™ unbound.

It’s about that time. With Vol. 6 coming to a close, we wanted to take a moment to share back some insights and feedback that we’ve collected over the course of the volume. 

As mentioned in our Y2 Roadmap Blog, your feedback during this year will help shape the future of the franchise, and part of our commitment back to you is being transparent about what we’re hearing along the way to ensure that it’s accurate, and sharing our point of view in response.

But first, let’s take a look at some gameplay data observed during Vol. 6:

S5 more popular than the R8? South Koreans and Australians the biggest night owls of the bunch? Much to think about. Head over to the community-run Subreddit and Discord channel to let the debate rage. We’d also love to hear what else you’d like to see in future End of Volume Report infographics.

Now, onto your feedback. There’s a few important disclaimers we need to share before getting into it:

• The majority of your feedback won’t be addressed during this year of live service. We’re a small team on a tight schedule and are working hard to bring you everything we’ve promised. We’ll make updates and refine features where possible, but most of the feedback is being collected to inform how we approach things in the future.
• We will only be including feedback in these reports that relates to what we’re doing in Unbound. There are certain frequent community requests (think we all know what we’re talking about here) that are outside of the scope of this project, and making any short statement about them would be unhelpful. Know that it’s heard and that your enthusiasm is appreciated, but we won’t be addressing those requests in these End of Volume Reports.   
• We’re focusing on responding to top feedback that has a more or less singular idea to share . Some of the top comments (particularly on Reddit) are long and address several different things or make many different requests. Trying to address them all in this already long blog post could get out of hand and potentially be confusing. But we’ve seen them all, hear you, and are trying to address what we can.

If you’re new to the game and want a recap of the features we’re discussing below, please visit the Vol. 6: Head to Head reveal blog.

Alright, let’s goooooo!

TOP FEEDBACK FOR DEDICATED PVP MODE

Most liked reply on Twitter : 

• “A much smoother experience when wanting to switch PVP playlists or going from PVP to Free Roam. Both require a full sign out and back in of Online services atm, it’s incredibly slow. Even if you just want to take a break you have to back out of online play, big vibe killer.” 

Dev Response : We made some changes to this flow already, ensuring that you are now taken back into the Garage so you can see your Speed Pass progression and if you want to make any vehicle changes before going back into PVP or switching to Freedrive. We hear you though and there are more improvements we could make for sure with regards to our flows and menu navigation's. We are looking into what could be possible in a future update

Most liked comment on Instagram :

• “As a person who came back to unbound I can say I want to grind for the rewards and that the game is BACK”

Dev Response : Really glad to hear this! There is much more we would like to do with PVP too and certainly we have learnt a lot already on how we would build something like this into a future installment of NFS from the start.

We saw lots of positive sentiment around the PVP update overall. There are few replies around PVP switching flow, and asking for the checkpoint system to be a bit more forgiving (closer to Heat’s version, whereby your speed is maintained when spawning) or larger in size. 

Dev Response : Checkpoints and reset speed is something we could do, but it could have some serious knock-on effects for how people are used to playing. We will take a closer look for the future but we likely won’t touch it this year because of the risk involved.

In addition, we see that more ‘player engagement opportunities’ would be appreciated, such as emoting (GG, nice race, get gd noob, etc.) with other players in the lobby, seeing opponents cars/player models, or ‘track maps’ prior to the events. 

Finally, other requests included allowing people to toggle whether or not they race with custom builds or stock builds - with level(ish) playing fields. To add to this, offering B-S+ classes all the time would be good (rather than 1 class a week) but of course both of these may result in smaller lobby sizes. 

Dev Response : We’re always looking at the best way we can maximise variety and fairness for players to experience the Volumes’ offerings. Candidly, it’s worth noting that we’re building on top of an existing system which isnt as agile as we would like it to be.

TOP FEEDBACK FOR WEEKLY PVP PLAYLISTS

Most liked reply on Twitter :

• “PVP is great and truly fresh breath for NFS, the only downside as I see lack of proper rewards for dedicated people who spends a lot of time in lobbies, both from LVL reward and rewards for Wins etc, I would suggest add decals for each level maybe, or for some milestones.” 

Dev Response : Glad to hear this! We do have a bunch of challenges associated to playing PVP and things like titles you can unlock from completing them which you can then show off during resulting and loading screens. We have lots of data coming in on levels and the amount of grind which we are looking into too. If it makes sense to make changes here, we certainly will.

• “Before starting the playlist, we need to see the race route when choosing a car.”

Dev Response : This is something we have been looking into but unfortunately is one of those ‘seems easy but isn't’ things. That being said, we are still investigating how we could make some changes here. We understand that you want to know the best car from your arsenal that will dominate for the route ahead

Most upvoted comment on Reddit :

• “I'd definitely like to see some Underground-themed playlists next volume, with a focus on tight inner-city racing in lower-end cars. I'd also like to see the currently playlist-exclusive events (like Solar Cycle and Dark Night) be opened up to more playlists, both within dedicated PvP and within the freeroam playlists”

Dev Response : You will definitely see some Underground-themed playlists for Vol. 7! With regards to the specific tracks there are opportunities to play these in Free Roam as it operates a similar rotation of events through the weeks. We are investigating ways in which we can update the cadence further as we did during the volume, striking the balance between variety and repetition.

Feedback on the Weekly PVP Playlists is similar to what we heard for the Dedicated PVP Mode. Lots of comments about greater variety in PVP (or perhaps faster cycling between playlists) - with variety being a key factor in keeping people motivated. Also some requests for ‘no contact’ races as well, whereby you would ghost through competitors (to avoid griefing). 

TOP FEEDBACK FOR AUDI IS BACK

• “Definitely carry over the Audi handling model to the rest of the car roster. I don't think it's fair for a handful of cars to get the new handling but not the rest of the roster. Some cars built entirely with grip in mind and no drift entry enabled still understeer.”

Dev Response : We are really glad to hear that the handling changes have been received so well. We would love to be able to roll this out across all our vehicles but the truth is that it takes a whole bunch of time to get each car we add to this quality, and we currently only have one handling designer. Whilst he is super human this is too tall of an order even for him. That being said, all of the new cars we add to the game (through Speed Pass) will have the new handling and we will look to add more where we can and when it makes sense.

• “The Handling especially the R8 is very good. Also the sound improvement is great. Maybe older Audi’s like the RS2 Avant or the old rally Audis would be fantastic. Solid work guys keep this up 👏”

Dev Response : Again, we love to hear it! The handling changes are actually part of future thinking we were already investigating so glad to see we are going in the right direction. As far as adding older Audis, this won’t be happening this year. Because our cars are fully customizable in the way they are, they take us a very long time to make, and the new car plan for the rest of the year is already set.

We also hear your comments about the new handling model potentially being OP, especially compared to muscle cars which are perceived as too slow/heavy in comparison. 

TOP FEEDBACK FOR RANK

• “Personally I think every time you level up maybe the cars should be unlocked instead of having to do really monotonous challenges for them there are enough levels for them all to be unlocked so please change the way the regular cars are unlocked in lakeshore online.”

Dev Response : This is great feedback and we hear this. We are looking into ways that can make unlocking of cars for MP easier or in potentially different ways, more to come on this in the near future.

• “I think rank system is a nice addition to the game, good indicator for “street credit” in multiplayer. It’s a nice stat to have and i’ve been visiting multiplayer more often in order to rank up. Rewards should be more engaging, let’s say 4 rewards, each one after 50 levels, lvl 1 - banner + title, lvl 50 clothing, lvl 100 emote, lvl 150 driving effect, lvl 200 custom and original car with matching customisation to the clothing and driving effect that we grinded earlier. For the moment rewards have 0 value for me to be brutally honest. Progression time is good.”

Dev Response : Great feedback again. we are looking into the Rank system as a whole and hope to update on it soon. While doing this we will think about ways and what we could add as rewards when you Rank. A more in depth system of Ranking by skill and earning is probably out of scope for Kaizen, it is, however 100% something we would be considering for anything in the future alongside a more dedicated space for pure racing skill.

TOP FEEDBACK FOR NFS LEGENDS CONTENT

• I’m only asking for one thing. Can you please add the soundtracks of the 90s Need for Speed games to Need for Speed Unbound? And while you’re at it, can we please finally have them on Spotify? Those soundtracks are my childhood and deserve to be preserved.

Dev Response : Ultimately, this comes down to licensing costs, because artists deserve to be compensated for their work. Songs are licensed for individual games, often have an expiration date, and would require new licensing contracts to bring to Unbound. This gets very expensive, very quickly and is out of scope for this year. We understand that music is very important to the Need for Speed experience, and this is something we’ll continue to pay attention to even if we have no plans to share right now. With regards to the publishing request, we still can’t make any promises but this is something we need to investigate going forward because we too have noticed some old NFS exclusives that aren’t available on streaming platforms and personally would like to see them there. Might not be possible, might have to wait for the right moment, but trust that we’re paying attention.

Aside from the music request, overall it seems you’ve really enjoyed the nostalgic content we’ve been bringing to NFS Unbound. This will really kick off in force starting with Vol. 7: Drift & Drag, inspired by NFS Underground 1&2, and continue through the rest of the year. 

The other main request regarding this topic is the Feedback That Must Not Be Named, that we’ve already said we won’t address in this particular blog LOL.

SEE YOU SOON

Thank you all so much for being part of this journey, as we continue to build towards the Ultimate NFS Experience in one place for the first time. We hope that we’ve accurately captured your feedback here, but if you disagree then feel free to hit us up on Instagram or Twitter ,or head over to the community-run subreddit or Discord channel .

See you on May 21st for the launch of Vol. 7: Drift & Drag.

    -Team Kaizen, Criterion Games

Need help? 

We got you. Hit up Answers HQ, where you can report bugs or issues for a member of the team to check out.

Be sure to follow Need for Speed on Twitter , Facebook , Instagram and TikTok for the latest news.

RELATED NEWS

Need for speed™ unbound vol. 7.0.1 patch notes, introducing dynamic catch-up packs and car sets for vol. 6-9, for this week’s theme we’re taking you all back to school… quattro school..

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• Published: 08 May 2024

The importance of distinguishing climate science from climate activism

• Ulf Büntgen   ORCID: orcid.org/0000-0002-3821-0818 1 , 2 , 3  

npj Climate Action volume  3 , Article number:  36 ( 2024 ) Cite this article

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I am concerned by climate scientists becoming climate activists, because scholars should not have a priori interests in the outcome of their studies. Likewise, I am worried about activists who pretend to be scientists, as this can be a misleading form of instrumentalization.

Background and motivation

It comes as no surprise that the slow production of scientific knowledge by an ever-growing international and interdisciplinary community of climate change researchers is not feasible to track the accelerating pace of cultural, political and economic perceptions of, and actions to the many threats anthropogenic global warming is likely to pose on natural and societal systems at different spatiotemporal scales. Recognition of a decoupling between “normal” and “post-normal” science is not new 1 , with the latter often being described as a legitimation of the plurality of knowledge in policy debates that became a liberating insight for many 2 . Characteristic for the yet unfolding phenomenon is an intermingling of science and policy 3 , in which political decisions are believed to be without any alternative (because they are scientifically predefined) and large parts of the scientific community accept a subordinate role to society (because there is an apparent moral obligation) 4 .

Motivated by the continuous inability of an international agreement to reduce greenhouse gas emissions to tackle global warming, despite an alarming recent rise in surface temperatures and associated hydroclimatic extremes 5 , I argue that quasi-religious belief in, rather than the understanding of the complex causes and consequences of climate and environmental changes undermines academic principles. I recommend that climate science and climate activism should be separated conceptually and practically, and the latter should not be confused with science communication and public engagement.

Climate science and climate activism

While this Comment is not a critique of climate activism per se, I am foremost concerned by an increasing number of climate scientists becoming climate activists, because scholars should not have a priori interests in the outcome of their studies. Like in any academic case, the quest for objectivity must also account for all aspects of global climate change research. While I have no problem with scholars taking public positions on climate issues, I see potential conflicts when scholars use information selectively or over-attribute problems to anthropogenic warming, and thus politicise climate and environmental change. Without self-critique and a diversity of viewpoints, scientists will ultimately harm the credibility of their research and possibly cause a wider public, political and economic backlash.

Likewise, I am worried about activists who pretend to be scientists, as this can be a misleading form of instrumentalization. In fact, there is just a thin line between the use and misuse of scientific certainty and uncertainty, and there is evidence for strategic and selective communication of scientific information for climate action 6 . (Non-)specialist activists often adopt scientific arguments as a source of moral legitimation for their movements 6 , which can be radical and destructive rather than rational and constructive. Unrestricted faith in scientific knowledge is, however, problematic because science is neither entitled to absolute truth nor ethical authority 7 . The notion of science to be explanatory rather than exploratory is a naïve overestimation that can fuel the complex field of global climate change to become a dogmatic ersatz religion for the wider public. It is also utterly irrational if activists ask to “follow the science” if there is no single direction. Again, even a clear-cut case like anthropogenically-induced global climate change does not justify the deviation from long-lasting scientific standards, which have distinguished the academic world from socio-economic and political spheres.

The role of recent global warming

Moreover, I find it misleading when prominent organisations, such as the Intergovernmental Panel on Climate Change (IPCC) in its latest summary for policymakers 5 , tend to overstate scientific understanding of the rate of recent anthropogenic warming relative to the range of past natural temperature variability over 2000 and even 125,000 years 8 , 9 , 10 , 11 . The quality and quantity of available climate proxy records are merely too low to allow for a robust comparison of the observed annual temperature extremes in the 21st century against reconstructed long-term climate means of the Holocene and before. Like all science, climate science is tentative and fallible 7 . This universal caveat emphasises the need for more research to reliably contextualise anthropogenic warming and better understand the sensitivity of the Earth’s climate system at different spatiotemporal scales 12 . Along these lines, I agree that the IPCC would benefit from a stronger involvement in economic research 13 , 14 , and that its neutral reports should inform but not prescribe climate policy 3 , 15 .

Furthermore, I cannot exclude that the ongoing pseudo-scientific chase for record-breaking heatwaves and associated hydroclimatic extremes distracts from scientifically guided international achievements of important long-term goals to reduce greenhouse gas emissions and mitigate global warming 16 . It is therefore only a bitter irony that the partial failure of COP28 coincided with the warmest year on record 17 , 18 , 19 . The temporal overshoot of 2023 now challenges the Paris Agreement to keep global warming well below 2 °C 20 . The IPCC’s special report 21 on exactly this scientifically questionable climate target 20 can be understood as a useful example of science communication that fostered a wide range of climate action 22 . The unprecedented recent temperature rise that follows increasing greenhouse gas concentrations 23 and has been amplified by an ongoing El Niño event 24 is likely to continue in 2024. This unparallel warming, however, has the unpleasant potential to trigger a dangerous zeitgeist of resignation and disregard—If it happened once, why shouldn’t it happen twice?

A way forward

In essence, I suggest that an ever-growing commingling of climate science, climate activism, climate communication and climate policy, whereby scientific insights are adopted to promote pre-determined positions, not only creates confusion among politicians, stakeholders and the wider public, but also diminishes academic credibility. Blurring boundaries between science and activism has the potential to harm movements of environmentalism and climate protection, as well as the much-needed international consent for sustainable growth and a global energy transition. If unbound climate activism results in widespread panic or indifference, people may think that it is either too late for action or that action does not matter. This argument is not in disagreement with the idea that mass mobilisation as an effective social response to climate change is only possible if society is experiencing sustained levels of risk 25 . Nevertheless, I would argue that motivations are more helpful than restrictions, at least in the long run. My criticism of an uncontrolled amalgamation of climate scientists and climate activists should not be understood as a general critique of climate activism, for which there are many constructive ways 26 , especially when accepting that climate mitigation and adaptation are both desirable options, and that non-action can be an important part of activism.

In conclusion, and as a way forward, I recommend that a neutral science should remain unbiased and avoid any form of selection, over-attribution and reductionism that would reflect a type of activism. Policymakers should continue seeking and considering nuanced information from an increasingly complex media landscape of overlapping academic, economic and public interests. Advice from a diversity of researchers and institutions beyond the IPCC and other large-scale organisations that assess the state of knowledge in specific scientific fields should include critical investigations of clear-cut cases, such as anthropogenic climate change. A successful, international climate agenda, including both climate mitigation and adaptation, requires reliable reporting of detailed and trustworthy certainties and uncertainties, whereas any form of scientism and exaggeration will be counterproductive.

Funtowicz, S. O. & Ravetz, J. R. Three types of risk assessment: a methodological analysis. In Risk Analysis in the Private Sector (eds. Whipple, C. & Covello, V. T.) 831–848 (Plenum Press, New York, 1885).

Ravetz, J. & Funtowicz, S. Post-normal science—an insight now maturing. Futures 31 , 641–646 (1999).

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von Storch, H. COVID-19 und menschgemachter Klimawandel als postnormale wissenschaftliche Objekte. Naturwiss. Rundsch. 74 , 132–136 (2021).

IPCC. Summary for policymakers. In Climate Change 2021: the Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (eds. Masson-Delmotte, V. P. et al.) 3–32 (Cambridge University Press, Cambridge, 2021).

Sofdorf, A. & Burgi, V. Listen to the science!”—the role of scientific knowledge for the Fridays for Future movement. Front. Comm. 7 , 983929 (2022).

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Acknowledgements

This study was supported by the Centre for Interdisciplinary Research (ZiF), Bielefeld, Germany, the Czech Science Foundation (# 23-08049S; Hydro8), the ERC Advanced Grant (# 882727; Monostar) and the ERC Synergy Grant (# 101118880; Synergy-Plague).

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Partition vs. Volume: What’s the Difference? 

Partition vs. Volume: Explore partitions and volumes, explain the differences between them, and their context in the world of data storage.

• Future of Data Storage

May 09, 2024

Partitions and volumes are extremely important topics in the broader category of data storage, playing key roles in how data information is organized and accessed. When you understand their relationship, you can gain deeper insights into the intricacies of data storage and its possibilities. In this blog post, we’re going to explore partitions vs. volumes, explain the differences between them, and shed some light on their capabilities–especially in virtualized environments .

What is a Partition in Data Storage?

A data partition is a very important part of data storage, but to understand it, we have to first understand logical distinction . When we say something is logically distinct, we mean that while the thing’s physical structure doesn’t get changed, we can alter the ways it gets interacted with and organized using conceptual or functional rules. 

Imagine a library: the physical structure houses books. The logical distinction is how you organize the books. The books can be sorted and stored following any file structure or organizational method you like. You can have multiple copies of the same book to make discovery easier, or you can have lots of index card placeholders that point you to where to find the one copy of each book. Your organizational method (logical distinction) doesn’t affect the building (physical storage).

In data storage, a partition refers to the creation of a logically distinct section of a storage device. Once a partition has been created, it can be treated as a separate unit of storage by the operating system. Depending on a storage device’s capacity, you can partition it into multiple sections, and each one would have its own file system and directory structure.

To use our earlier example, maybe you have a huge building that houses a library with a fiction section (which has one copy of every book, organized by author) and a non-fiction section (which has multiple copies of books, organized by genre). The two sections are partitions of the bigger building.

What Does a Partition Do?

Partitions play a very important role in storage systems. Among other benefits, a partition enables organization, isolation, multi-boot systems, performance, and security and access control and makes them easier to manage.

Partitions make it possible to organize data storage devices so that each area is dedicated to a specific purpose, from operating system files to application files and more. Since partitions act as distinctly separate entities, they’re separated from one another. This isolation helps safeguard against data corruption or loss. Multi-boot systems tend to rely on partitions, allowing users to use different operating systems for different purposes. Partitioning can lead to better performance when frequently accessed files are grouped together. And last, being able to set different access permissions or encryption schemes on different partitions can enhance security for sensitive data.

What is a Volume in Data Storage?

A volume is a single accessible storage area with its own file system. A volume is a logically distinct entity, representing a formatted section of a physical or virtual storage device. Importantly, an operating system treats a volume as a distinct unit, capable of storing files, directories and other data.

The logical distinction that defines a volume leads to more efficient organization and management of data. Each volume can have its own set of permissions, encryption and storage policies. Volumes are important for data backup and recovery and help minimize the impact of data loss or corruption. A volume is the unit a system uses for backup and restore processes.

Volumes also play a crucial role in virtualized environments. Virtualized systems and networks are already, by definition, abstracted. But the virtual disks that virtual machines (VMs) use to store their operating systems, applications and data can be virtualized volumes within the underlying storage infrastructure. In practice, virtual volumes are basically segments of storage carved from the pool of flash storage. These segments get presented to VM hosts as logical disks. 

As an example, see Pure Storage’s support of VMware vVols (virtual volumes) in their FlashArray product line: these virtual volumes are similar to traditional volumes, but they’re much more flexible and dynamic.

What’s the Difference Between a Partition and a Volume?

A volume and a partition aren’t the same thing. They describe different ways of delineating and organizing digital storage systems, and while they’re related to one another, there are important distinctions.

If you were to define a book, you could do so hierarchically: a book contains pages, pages contain paragraphs, and paragraphs contain words. Those terms have a hierarchical relationship. Volumes and partitions don’t have a perfect hierarchical relationship.

A partition is a logical division of a disk (physical or virtual). A volume is a logical assembly of one or more partitions which the operating system knows how to use as a mass storage container.

To help illustrate the difference between a partition and a volume, imagine an office building partitioned into individual offices. When a company moves in, maybe they group their departments by floor (payroll on the first floor, IT on the second floor, management on the third floor, etc.). Time passes and the company reorganizes: it moves some payroll employees to the second floor, and puts an IT tech support professional on each floor. They do this without changing the size of any of the offices. You could imagine the building as the disk drive, offices as the partition, and the organizational structure of the company as the drives.

Another way to imagine the difference between a partition and a volume is a filing cabinet. A filing cabinet represents the disk drive. Each filing cabinet drawer is a partition. Creating volumes would be like labeling the top two drawers for “Project Alpha” and the bottom two drawers for “Order 66.” Project Alpha files and folders are alphabetized while Order 66 files and folders are organized by date.

What these two analogies illustrate is that partitions and volumes are both logical distinctions within a file system, but what they’re separating and providing access to is different. Something that makes the distinction between partition and volume even more challenging is the fact that Windows has used the terms interchangeably. So while a partition is clearly defined, “volume” can sometimes be less concrete and more context-dependent.

What Virtual Volumes and Virtual Partitions Are Capable Of

Partitions and volumes serve as logical separations in data storage systems, enabling complex organization and control services. Their importance becomes even more pronounced in virtualized environments.

Data deduplication , the process of eliminating duplicate copies of data within a volume or storage system, is an extremely common challenge. Although it may seem straightforward, deduplication and compression are actually very hard especially considering traditional physical limitations on storage capacity. 

However, there are companies making strides in developing top-tier data reduction and deduplication advances, like Pure Storage (best known for their on-prem, all-flash storage solutions). These advancements owe much to innovations related to virtual volumes and partitions. For instance, products like Portworx® leverage these advancements to provide fully integrated, persistent, automated capacity management for applications running on Kubernetes .

Partitions and volumes are core concepts in data storage, each with a distinct role. While a partition is a logically distinct section of a storage device, a volume is a single accessible storage area with its own file system. They’re closely related, but not always interchangeable. 

In practice, partitions and volumes enable efficient organization of data while streamlining access and management. When leveraged in virtual environments in particular, they can provide never-before-seen capacity, speed and efficiency.

Written By: Pure Storage

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Trump's hush-money verdict hinges on a single piece of paper. See the most important evidence in the case.

• People's Exhibit 35 is key evidence in the Donald Trump hush-money trial.
• It documents the hush-money payment and an alleged conspiracy to falsify its reimbursement.
• But whether Exhibit 35 will clinch or crash the district attorney's case depends on Michael Cohen.

Welcome to People's Exhibit 35, the single most important piece of evidence in the Donald Trump hush-money trial .

You'll see this one-page document in its succinct entirety just a few paragraphs down. Then, I'll walk you through it, section by section.

People's 35 is the fulcrum for the entire case. As they make their closing arguments this week, prosecutors are sure to say it proves Trump is guilty, while the defense will say it proves he's innocent.

And which side wins will depend in large part on whether jurors believe the key prosecution witness, Michael Cohen, who testified last week that Trump personally saw — and approved — the document's contents.

People's 35 looks a little complicated, but I promise this won't hurt a bit. Go ahead, scroll through it, just to see what it looks like, and I'll meet you on the other side, where we'll take it apart.

As shown above, People's 35 is a one-page bank statement from October 2016 for something called "Essential Consultants," an LLC controlled by Cohen.

The section highlighting, but not the handwriting, is mine.

It may not look like a lot, but I bet you when prosecutors found this hard-copy sheet of paper among hundreds of thousands of pages of subpoenaed Trump Organization documents , somebody shouted, "Holy @#$%!!!!"

People's 35 encapsulates almost the entirety of the alleged hush-money-conspiracy . It has almost everything, and all on one page.

The third block I've highlighted from the top shows Cohen wired $130,000 of his own money to a lawyer for the porn star Stormy Daniels on October 27, 2016, just 12 days before the election. That, for anyone who's sleeping through the trial , is the hush money.

The shaded block at the bottom right? That's where Cohen scribbled that Trump owed him $180,000, which is the hush money plus a $50,000 outlay Cohen previously made. (That "tech services" outlay is a funny story of its own, which we'll get to.)

And the bottom-left block shows where Trump's former top money man, his chief financial officer Allen Weisselberg , scratched out how much Cohen was owed. Weisselberg then worked out how that total would be (allegedly illegally) doubled to account for income taxes and how that grand total would then be (allegedly illegally) reimbursed.

No fingerprints, though

Yes, People's 35 has almost everything — the $130,000 hush-money payment itself and the actual chicken-scratched math behind what prosecutors call a conspiracy to falsify the business records for Cohen's reimbursement.

What People's 35 doesn't have is Trump's fingerprints, a point that the defense is sure to press during closing arguments.

To connect Trump to the alleged scheme, jurors will need to believe Cohen — who told them last week that when all the calculating and scribbling was done, he and Weisselberg marched this very page into Trump's office on the 26th floor of Trump Tower in Manhattan.

It was mid-January 2017, and Trump was days away from his inauguration.

Prosecutors say Trump's schedule was packed at the time with teleprompter training sessions and meetings with his future chief of staff, Reince Priebus.

But Trump carved out a moment nonetheless to sit with Weisselberg, his loyal CFO, and with Cohen, his attorney, who prosecutors say had just fronted $130,000 of his own cash to pay off a porn actor and was eager for repayment.

The defense counters that this meeting never happened and that Cohen and Weisselberg are solely responsible for any falsified documents.

They are expected to argue that Trump was too busy running the country in 2017 to have had a hand in the year's worth of bogus monthly "retainer" checks that reimbursed Cohen — including nine checks he signed personally .

'He approved it'

"Did he show this document to Mr. Trump?" the prosecutor Susan Hoffinger asked Cohen during direct testimony on Monday, the "he" being Weisselberg.

"Yes," Cohen answered as Trump watched from the defense table.

"And what, if anything, did Mr. Trump say at the time?" the prosecutor asked.

"He approved it," Cohen answered, referring to Trump. "And he also said, 'This is going to be one heck of a ride in DC.'"

Ready? Here's a closer look, starting with the highlighted section at the top.

Prosecutors allege that less than two weeks before the 2016 election, Cohen tapped his own home-equity line of credit in order to purchase Daniels' silence.

But Cohen obscured his role as a hush-money bag man. Instead of sending the money directly, he first wired the $130,000 into the bank account for a newly created shell company called Essential Consultants LLC.

The LLC's sole purpose was to handle the hush-money payment, Cohen testified.

"Can we put up People's Exhibit 35, please, in evidence?" Hoffinger, the prosecutor, asked just after Monday's lunch break.

The document was displayed on personal screens for each of the jurors, and on four large overhead screens for the audience.

"Do you recognize this document?" Hoffinger asked.

"I do," Cohen answered. "This is the bank statement for Essential Consultants for the period of October 26th of 2016 through the 31st of October of 2016," Cohen explained.

Next, let's turn to the highlighted section below.

Here, we see the $130,000 hush-money payment moving into, and then out of, the Essential Consultants bank account.

Cohen testified last week that he took the money from his HELOC so he could hide the big outlay from his wife.

Her name was on the HELOC, but the billing was paperless, Cohen explained.

"You decided to do it this way, it was quick, you could move the money quickly, because you wanted to conceal it from your wife, correct?" the defense lawyer Todd Blanche asked Cohen during cross-examination on Thursday.

"Correct," Cohen answered.

Related stories

Let's move to the third section from the top, highlighting where the money went.

So long, hush money.

People's Exhibit 35 shows that on October 27 — only 12 days before the election — Cohen wired the $130,000 from Essential Consultants to Keith Davidson, who was Daniels' lawyer at the time.

Davidson also repped Karen McDougal , a former Playboy Bunny who'd been paid $150,000 just weeks prior to keep her silent about a nearly yearlong affair she said she had with Trump.

Both the porn star and the pinup model say they slept with Trump at the same Lake Tahoe celebrity golf tournament in 2006. Trump's son with Melania Trump was then four months old.

Trump has consistently denied having sex with the two women.

Davidson's testimony in early May was noteworthy for its name-dropping. The attorney told jurors he peddled salacious celebrity stories to the National Enquirer, including stories targeting Charlie Sheen, Hulk Hogan, Lindsay Lohan, and Tila Tequila.

The defense used its cross-examination of Davidson to imply that Trump was no mastermind and was instead a helpless victim of something akin to celebrity extortion.

Next: Cohen's handwriting, highlighted in the bottom-right corner.

Here is where Cohen testified that he made a jotted note of another personal outlay Trump owed him for, on top of the $130,000 and the wiring fee of $35.

This was a reimbursement for $50,000 paid to the Virginia tech company RedFinch Solutions LLC.

RedFinch did polling for the Trump campaign and set up the Twitter account @WomenForCohen , touting him as a so-called "pit bull" and "sex symbol."

"He told me to add up the 130 with the 50,000 for RedFinch — total it to 180,000," Cohen testified Monday, referring to a talk he said he had with Weisselberg before the two men marched People's 35 into Trump's office.

Cohen never reimbursed RedFinch for the whole $50,000, he testified.

Finally, let's look at the bottom-left section.

"And whose handwriting is at the bottom left and middle?" Hoffinger, the prosecutor, asked Cohen as People's 35 was displayed.

"That's Allen Weisselberg's," Cohen answered.

Weisselberg has been unavailable to testify. He's serving a five-month perjury sentence for lying on Trump's behalf at last year's civil fraud trial.

"And how were you able to recognize Allen Weisselberg's handwriting?" the prosecutor asked.

"Well, I recognize the handwriting, but I was also there in the room when he was writing it," Cohen answered.

Weisselberg, in his handwritten note, started with the $180,000 Cohen said Trump owed him.

The CFO underlined the amount. Below that, he wrote, "Grossed up to $360,000."

"He told me what he was going to do was to — it's called 'gross it up,'" Cohen explained to the jury.

Weisselberg's idea — approved by Trump — was to falsely process Cohen's $180,000 reimbursement as legal fees, paid in monthly installments throughout 2017, Trump's first year in office, prosecutors say.

But because Cohen faced a 50% tax penalty on that income, Weisselberg doubled — or "grossed up" — the $180,000, Cohen testified.

"So in order to get back the 180, what he did was, he then wrote down 360,000," Cohen testified. Cohen could then take his 50% tax hit, paying the IRS $180,000 and still pocketing the $180,000 he was due.

Weisselberg tacked on an extra $60,000 year-end bonus, arriving at a grand total of $420,000, Cohen testified, continuing to translate the CFO's handwriting to jurors.

Cohen said he was told the $420,000 should be divided into monthly "retainer" checks of $35,000.

That was bad news for Cohen, who'd walked into the meeting with Weisselberg and Trump assuming he'd be reimbursed in one lump sum.

But Trump and Weisselberg had figured it all out in advance, Cohen said he soon realized.

"Did Mr. Weisselberg say in front of Mr. Trump that those monthly payments would be, you know, like a retainer for legal services?" Hoffinger asked Cohen.

"Yes," Cohen answered.

"Did you say something to the effect of that you had the sense that they had spoken about this previously?" Hoffinger asked.

"Why do you say that?" the prosecutor asked.

"Because they always played that sort of game — a 'frick and frack' type game," Cohen said.

People's 35 was still displayed on the courtroom's screens, both large and small, as Hoffinger asked what happened when Weisselberg "showed Mr. Trump this document."

"Did Mr. Trump try to renegotiate?" Hoffinger asked.

"No," Cohen answered.

"So he approved it at that point?" the prosecutor asked.

Closing arguments could come as soon as Tuesday, with jury deliberations starting as early as Thursday. Trump faces anywhere from no jail to four years in prison if convicted of felony falsification of business records.

Correction: May 20, 2024 — An earlier version of this story misstated the timing of Michael Cohen's $130,000 payment to Keith Davidson. It was 12 days before the 2016 presidential election, not 11 days.

Watch: The biggest bombshells from Trump's hush money trial

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Mothers’ employment has surpassed pre-pandemic levels, but the child care crisis persists.

The COVID-19 pandemic laid bare the precariousness of both employment and the caregiving infrastructure across the country. The huge shock to the economy, when coupled with the closure of schools and paid caregiving facilities, wreaked havoc on employment rates, and mothers’ employment in particular plummeted 15.7% from February to April 2020 *. While many mothers stopped working during this time because their employers shut down, others left the labor force because they had no other option than to provide full-time care for their loved ones. 

Now, four years later, overall maternal employment has largely recovered from the steep declines experienced at the onset of the COVID-19 pandemic. In fact, the share of employed mothers is 1.9% higher now than in February 2020 , according to a Women’s Bureau analysis of the Current Population Survey . And while the speed of employment recovery varied for different groups of mothers, as of February 2024, maternal employment has more or less recovered for most groups of moms. For many groups of mothers – Asian moms, Hispanic moms, those with a bachelor’s degree and those whose youngest child is younger than six years – employment rates now exceed pre-pandemic levels. For other groups of mothers – those with less than a bachelor’s degree and those whose youngest child is 13 to 17 years old – employment rates now hover around pre-pandemic levels. 

ACROSS MANY DEMOGRAPHIC GROUPS, MORE MOMS ARE EMPLOYED NOW THAN PRIOR TO THE COVID-19 PANDEMIC  Percent Change in Mothers’ Employment in February 2024 Relative to February 2020 

One factor that may have contributed to the growth in employment for some U.S. mothers is the increasing prevalence of telework. In 2023, about 24.2% of mothers reported working from home at some point in the prior week, with rates rising to 26.8% among mothers with whose youngest child is under the age of six, according to a Women’s Bureau analysis of the Current Population Survey. 

Although telework may be a valuable strategy for integrating work and family responsibilities for some, it is by no means a panacea . Many jobs – particularly service jobs, healthcare occupations and jobs in education – often do not offer telework options. Similarly, telework is often unavailable for those with less education: While 34% of mothers with only a bachelor’s degree and 36% of mothers with an advanced degree reported teleworking in the prior week, only 4% of mothers with less than a high school diploma reported teleworking. And even for those workers who can access it, telework is not a substitute for adequate, accessible and affordable child care . Indeed, child care availability has become even more constrained as many child care providers closed permanently or lost workers during the pandemic.   

When a family has child care issues, mothers miss work or reduce work hours more often than fathers. In 2023, among employed parents who did not work in the prior week, 3.1% of mothers and 1.1% of fathers reported child care problems as the reason for not working, according to a Women’s Bureau analysis of the Current Population Survey. Similarly, among employed parents who normally worked full-time but worked part-time in the prior week, 3.9% of mothers and 1.5% of fathers reported child care problems as the reason for working fewer hours. 

MORE MOMS THAN DADS TAKE TIME OFF WORK FOR CHILD CARE  Percent of Employed Parents Who Did Not Work or Worked Part-Time in the Prior Week Due to Child Care Problems   

Expanding and strengthening the U.S. care infrastructure could help alleviate these work disruptions and likely bolster mothers’ employment. Research from the Women’s Bureau finds that a 10% decrease in median child care prices in a county is associated with a 1% increase in maternal employment. Improving the care infrastructure also means ensuring quality jobs and family-sustaining wages for child care workers .

Expanded access to policies like paid family and medical leave could also improve stability in employment hours among those employed and reduce gender disparities in labor supply. While maternal employment has recovered and even exceeded pre-pandemic levels, the employment rate of mothers (71.7% in February 2024) remains far lower than that of fathers (92.0%). Estimates suggest that if the U.S. had a labor force participation rate similar to Canada or Germany – countries that both have national paid leave   and more comprehensive family-supporting policies – the number of women employed would increase by about 5 million and generate over $775 billion in economic activity a year . Although their employment has finally returned to pre-pandemic levels, the lack of a robust care infrastructure may   continue to prevent mothers from achieving their full potential in the labor force.

*Unless specified otherwise, data applies to mothers ages 25 to 54 with children under 13.

Erin George is an Economist at the Women’s Bureau.

• Women's Bureau

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