What Is Cost Variance Percentage (CV%) in EVM?

<div class="ge-article-wrapper"><article class="ge-article-body"><p>Cost Variance Percentage expresses the <a href="/en/earned-value/definitions/cost-variance">cost variance</a> as a proportion of <a href="/en/earned-value/definitions/earned-value">earned value</a>, making it easier to compare performance across projects of different sizes. A CV% of -5% means the same thing whether the project is £5M or £50M.</p><p>This term is part of the <a href="/en/earned-value/definitions">earned value definitions glossary</a>.</p><h2>The Formula</h2><div class="ge-formula-box ge-anim"><span class="ge-formula-label">Formula</span><code>CV% = (CV / EV) x 100 = ((EV - AC) / EV) x 100</code></div><p>CV% is the inverse perspective of <a href="/en/earned-value/definitions/cost-performance-index">CPI</a>: if CPI = 0.95, then CV% = -5.3% (you're overspending by 5.3% of earned value).</p><h2>Threshold Scale</h2><div class="ge-table-wrap ge-anim"><table class="ge-table"><thead><tr><th>CV%</th><th>Status</th><th>Action</th></tr></thead><tbody><tr><td>> +5%</td><td>Under budget</td><td>Verify data accuracy</td></tr><tr><td>0% to +5%</td><td>Healthy</td><td>Monitor</td></tr><tr><td>0% to -5%</td><td>Marginal overrun</td><td>Investigate root cause</td></tr><tr><td>-5% to -10%</td><td>Significant overrun</td><td>Formal recovery plan</td></tr><tr><td>< -10%</td><td>Severe overrun</td><td>Escalate to board</td></tr></tbody></table></div><h2>Common Mistakes</h2><ol><li><strong>Using CV% without context.</strong> -3% in month 2 is noise. -3% in month 12 is a pattern.</li><li><strong>Comparing CV% across different project phases.</strong> Early phases often have higher variance due to mobilisation costs.</li></ol><div class="ge-product-note ge-anim"><p><strong>How Gather helps.</strong> Gather tracks CV% trends across all your projects from a single dashboard. <a href="https://gatherinsights.com/contact">Book a demo</a>.</p></div><h2>Frequently Asked Questions</h2><h3>What's the relationship between CV% and CPI?</h3><p>CV% = (1 - (1/CPI)) x 100. If CPI = 0.90, CV% = (1 - 1.111) x 100 = -11.1%. They convey the same information in different formats.</p></article></div>