What Is Baseline Execution Index (BEI)? Schedule Health Metric

<div class="ge-article-wrapper"><nav class="ge-toc" aria-label="Table of contents"><p class="ge-toc-label">In this article</p><ul class="ge-toc-list"><li><a href="#the-formula">The Formula</a></li><li><a href="#why-bei-and-spi-tell-different-stories">Why BEI and SPI Tell Different Stories</a></li><li><a href="#the-dcma-14-point-schedule-assessment">The DCMA 14-Point Schedule Assessment</a></li><li><a href="#worked-example-calculating-bei-on-a-highway-scheme">Worked Example: Calculating BEI on a Highway Scheme</a></li><li><a href="#common-mistakes">Common Mistakes</a></li><li><a href="#frequently-asked-questions">Frequently Asked Questions</a></li></ul></nav><article class="ge-article-body"><p>The Baseline Execution Index (BEI) measures whether your project team is actually doing the things the programme says they should be doing. Not the cost-weighted version. Not the earned value version. The raw, unforgiving count: how many activities that should be finished by now are actually finished? BEI is one of the 14 metrics in the DCMA schedule assessment framework, and it's the one that catches teams out because you can't hide behind favourable cost weighting.</p><p>BEI is part of the <a href="/en/earned-value/definitions">earned value definitions glossary</a>. For the cost-weighted equivalent, see <a href="/en/earned-value/definitions/schedule-performance-index">Schedule Performance Index (SPI)</a>, and for a full walkthrough of all the core formulas, visit the <a href="/en/earned-value/definitions">earned value formulas page</a>.</p><h2 id="the-formula">The Formula</h2><div class="ge-formula-box ge-anim"><span class="ge-formula-label">Formula</span><code>BEI = Number of tasks completed on time / Number of tasks that should be completed by now</code></div><p>That's it. No cost weighting. No earned value calculation. Pure task-count ratio.</p><p>The target threshold from the DCMA 14-point assessment is <strong>BEI >= 0.95</strong>. Anything below 0.95 means your programme is slipping in ways that the headline SPI might not show.</p><h2 id="why-bei-and-spi-tell-different-stories">Why BEI and SPI Tell Different Stories</h2><p>This is where it gets interesting. <a href="/en/earned-value/definitions/schedule-performance-index">SPI</a> weights progress by cost. BEI doesn't. That distinction matters enormously on construction projects where a handful of high-value packages dominate the budget.</p><pre class="ge-ascii-diagram ge-anim"> BEI vs SPI – How Cost Weighting Hides Problems ================================================ Programme with 50 activities due by Month 6: SCENARIO: 8 small activities are late, 1 large activity is ahead Activities due: 50 Completed on time: 42 (the 8 late ones are all small-value) BEI = 42 / 50 = 0.84 ← RED FLAG But in cost terms: EV = £4.8M (large piling package ahead of schedule) PV = £4.5M (planned value to date) SPI = £4.8M / £4.5M = 1.07 ← LOOKS FINE ┌─────────────────────────────────────────────────┐ │ SPI says: "Ahead of programme" │ │ BEI says: "42 of 50 tasks done – 8 are late" │ │ │ │ Which one do you trust? │ │ Answer: both. They measure different things. │ └─────────────────────────────────────────────────┘ </pre><p>SPI tells you about cost-weighted progress. BEI tells you about execution discipline. A project can have SPI > 1.0 and BEI < 0.80 at the same time, and that's a project heading for trouble, because those 8 late activities are probably predecessors to something critical.</p><p>I've seen this exact pattern on a £60M rail package. The SPI was 1.03 for three straight months. Everyone was relaxed. Meanwhile, 14 enabling works activities had slipped by two to three weeks each. They were low-value individually, fencing relocations, ecology surveys, access road improvements, but they were predecessor constraints on the main earthworks. When the earthworks crew finally mobilised, they couldn't start because three access points weren't ready. The SPI dropped from 1.03 to 0.78 in a single reporting period.</p><p>BEI would have flagged that at month 3. It didn't get calculated until month 7, after the damage was done.</p><h2 id="the-dcma-14-point-schedule-assessment">The DCMA 14-Point Schedule Assessment</h2><p>BEI sits within the Defence Contract Management Agency's 14-point schedule health check. It's a US DoD framework, but it's been adopted widely on UK infrastructure programmes, particularly on Network Rail, Highways England, and MoD contracts. The relevant metrics for BEI context:</p><div class="ge-table-wrap ge-anim"><table class="ge-table"><thead><tr><th>#</th><th>Metric</th><th>Threshold</th><th>What It Checks</th></tr></thead><tbody><tr><td>1</td><td>Logic (missing predecessors)</td><td>< 5%</td><td>Are activities properly linked?</td></tr><tr><td>2</td><td>Logic (missing successors)</td><td>< 5%</td><td>Do activities drive downstream work?</td></tr><tr><td>3</td><td>Relationship types</td><td>< 5%</td><td>Are you misusing SF/SS/FF links?</td></tr><tr><td>4</td><td>Hard constraints</td><td>< 5%</td><td>Are you forcing dates instead of using logic?</td></tr><tr><td>5</td><td>High float</td><td>< 5%</td><td>Are activities disconnected from the critical path?</td></tr><tr><td>6</td><td>Negative float</td><td>0%</td><td>Is the programme already showing delay?</td></tr><tr><td>7</td><td>High duration</td><td>< 5%</td><td>Are activities too long to manage?</td></tr><tr><td>8</td><td>Invalid dates</td><td>0%</td><td>Do any activities have dates in the past with no progress?</td></tr><tr><td>9</td><td>Resources</td><td>100%</td><td>Is every activity resource-loaded?</td></tr><tr><td>10</td><td>Missed tasks</td><td>< 5%</td><td>How many tasks are overdue?</td></tr><tr><td>11</td><td>Critical path test</td><td>Pass</td><td>Does the CP drive the completion date?</td></tr><tr><td>12</td><td><a href="/en/earned-value/definitions/critical-path-length-index">Critical path length index</a></td><td>>= 0.95</td><td>Is the CP achievable within float?</td></tr><tr><td>13</td><td><strong>BEI</strong></td><td><strong>>= 0.95</strong></td><td><strong>Are tasks being completed as planned?</strong></td></tr><tr><td>14</td><td>Cost/schedule integration</td><td>Pass</td><td>Is the schedule aligned with the cost baseline?</td></tr></tbody></table></div><p>BEI doesn't operate in isolation. A programme might pass BEI at 0.96 but fail metric 6 (negative float), meaning tasks are being ticked off but the overall completion date is still slipping because the critical path has been disrupted. You need the full picture.</p><h2 id="worked-example-calculating-bei-on-a-highway-scheme">Worked Example: Calculating BEI on a Highway Scheme</h2><span class="ge-worked-label">Worked Example</span><div class="ge-callout ge-anim"><p><strong>Scenario:</strong> A £35M NEC4 Option C dual carriageway improvement in West Yorkshire. The <a href="/en/earned-value/definitions/accepted-programme">Accepted Programme</a> has 210 activities. At the period 6 cut-off date (14 March 2025), the planner runs the BEI calculation.</p><p><strong>Step 1: Count activities due by 14 March 2025</strong> Filter the baseline programme for all activities with a baseline finish date on or before 14 March 2025. Result: <strong>48 activities</strong> should be complete.</p><p><strong>Step 2: Count activities actually complete</strong> Cross-reference against actual finish dates in the updated programme. Result: <strong>38 activities</strong> have an actual finish date on or before 14 March 2025.</p><p><strong>Step 3: Calculate BEI</strong> BEI = 38 / 48 = <strong>0.792</strong></p><p>That's well below the 0.95 threshold. Ten activities are late.</p><p><strong>Step 4: Investigate the late activities</strong></p><div class="ge-table-wrap ge-anim"><table class="ge-table"><thead><tr><th>Activity</th><th>Baseline Finish</th><th>Status</th><th>Impact</th></tr></thead><tbody><tr><td>Ecology survey (Section 3)</td><td>17 Jan 2025</td><td>Complete 04 Feb</td><td>Delayed fencing</td></tr><tr><td>Utility diversion (BT)</td><td>28 Jan 2025</td><td>In progress</td><td>Blocking drainage</td></tr><tr><td>Access road (Phase 2)</td><td>03 Feb 2025</td><td>Complete 21 Feb</td><td>Delayed earthworks start</td></tr><tr><td>Fencing relocation (Plot 7-12)</td><td>10 Feb 2025</td><td>Not started</td><td>Awaiting ecology</td></tr><tr><td>Trial holes (Bridge B)</td><td>14 Feb 2025</td><td>Complete 07 Mar</td><td>Delayed piling design</td></tr><tr><td>Temporary works design</td><td>21 Feb 2025</td><td>In progress</td><td>Blocking bridge erection</td></tr><tr><td>Ground investigation report</td><td>28 Feb 2025</td><td>Not started</td><td>Awaiting trial holes</td></tr><tr><td>Topographic survey (adj. Land)</td><td>03 Mar 2025</td><td>Complete 12 Mar</td><td>Minor delay</td></tr><tr><td>Environmental permits (EA)</td><td>07 Mar 2025</td><td>Awaiting approval</td><td>External dependency</td></tr><tr><td>Drainage design (Section 1)</td><td>14 Mar 2025</td><td>In progress</td><td>Blocking pipe installation</td></tr></tbody></table></div><p><strong>Analysis:</strong> The 10 late activities aren't random. There's a chain: ecology delayed fencing, which delayed earthworks access. Trial holes delayed the GI report, which delayed piling design. Two external dependencies (BT diversion, EA permits) are outside the team's control.</p><p>The BEI of 0.792 tells the commercial team: "Your programme is in trouble." But the breakdown tells them <em>where</em> and <em>why</em>. That's the value of BEI. It forces the conversation about specific activities, not abstract percentages.</p><p><strong>SPI comparison:</strong> Because the high-value earthworks (£8.2M) and structures (£6.1M) packages haven't started yet, SPI at this stage reflects only the enabling works, which are relatively low-value. SPI = 0.88. Still concerning, but less alarming than BEI's 0.792. The BEI tells the truer story here: nearly 21% of planned activities are late.</p></div><h2 id="common-mistakes">Common Mistakes</h2><p><strong>Confusing BEI with SPI.</strong> They aren't interchangeable. SPI is cost-weighted (<a href="/en/earned-value/definitions/earned-value">EV</a> / <a href="/en/earned-value/definitions/planned-value">PV</a>). BEI is task-weighted. On most construction projects, a few packages dominate the cost profile, so SPI can look healthy while BEI is screaming. Report both.</p><p><strong>Not filtering for the baseline finish date.</strong> BEI compares against the <em>baseline</em> programme, not the current forecast. If you're comparing against a re-sequenced programme, you're measuring against a moving target. Always use the original baseline finish dates (or the last formally approved re-baseline).</p><p><strong>Counting partially complete activities as complete.</strong> An activity that's 95% done isn't done. For BEI purposes, it's either finished or it isn't. Partial credit defeats the purpose of the metric. If you want to account for partial completion, that's what SPI is for.</p><p><strong>Ignoring the investigation step.</strong> A BEI of 0.84 is a signal, not a diagnosis. The value comes from asking <em>which</em> activities are late, <em>why</em> they're late, and <em>what they're blocking</em>. Teams that report BEI without the breakdown are ticking a box, not managing a programme.</p><div class="ge-product-note ge-anim"><p><strong>How Gather helps.</strong> Gather's AI reads your site diaries daily and maps progress against your cost-loaded programme, giving you accurate earned value data without manual spreadsheet updates. <a href="https://gatherinsights.com/contact">Book a demo</a> to see it working on a live NEC4 project.</p></div><h2 id="frequently-asked-questions">Frequently Asked Questions</h2><h3>What BEI score should I be targeting?</h3><p>The DCMA threshold is 0.95, meaning no more than 5% of activities should be late at any reporting point. In practice, most UK construction projects I've worked on hover between 0.85 and 0.92 during the enabling works phase, then tighten up once the main works are in full swing. Below 0.80 needs immediate intervention. Below 0.70 usually means the programme needs <a href="/en/earned-value/definitions/re-baselining">re-baselining</a> because too many activities have slipped to recover.</p><h3>Can BEI be greater than 1.0?</h3><p>Yes. If the team completes more activities than the baseline says should be done by now (perhaps by pulling work forward), BEI exceeds 1.0. On a 200-activity programme where 45 should be complete and 48 actually are, BEI = 48/45 = 1.067. That's a healthy position, but check it isn't artificial, teams sometimes close out easy activities early to boost the numbers while avoiding the harder ones.</p><h3>How often should I calculate BEI?</h3><p>Every reporting period, typically monthly on UK construction projects, aligned with your programme update cycle. Some projects on accelerated programmes calculate BEI fortnightly. The key is consistency: compare BEI across periods to spot trends. A BEI that drops from 0.96 to 0.91 to 0.84 over three months is telling you something the individual snapshots don't.</p><h3>Is BEI relevant on smaller projects?</h3><p>Less so. On a project with 40 activities, a single late task moves BEI by 2.5%. The metric becomes volatile and less meaningful. BEI works best on programmes with 150+ activities, where the statistical noise is lower and patterns become visible. For smaller projects, focus on the critical path and <a href="/en/earned-value/definitions/schedule-performance-index">SPI</a> instead.</p></article></div>