Enter your project's Planned Value, Earned Value, and Actual Cost to instantly calculate Cost Performance Index, Schedule Performance Index, Estimate at Completion, and Estimate to Complete. Pre-loaded with a realistic ₹2 Cr office fit-out example. Part of the VentureVitals AI Earned Value Management module.
| Index value | Performance rating | Cost Performance Index interpretation | Schedule Performance Index interpretation |
|---|---|---|---|
| > 1.05 | Exceptional | Under budget — check for scope reduction or unrealistic BOQ | Ahead of schedule — usually sustainable if resources are stable |
| 0.95 – 1.05 | On Track | Normal variance — monitor but no corrective action needed | On schedule — maintain current resource plan |
| 0.85 – 0.95 | Watch | Cost overrun developing — check for unraised variations, emergency material buying, BOQ errors | Behind schedule — Liquidated Damages risk if trend continues past 30% completion |
| 0.75 – 0.85 | Warning | Significant overrun — Extension of Time / variation order recovery needed now | Material delay — assess Liquidated Damages exposure, prepare Extension of Time application |
| < 0.75 | Critical | Severe overrun — 25%+ over Budget at Completion projected. Recovery unlikely without scope or contract renegotiation | Severe delay — Liquidated Damages cap likely being approached. Legal review required |
Note: Per PMBOK research, Cost Performance Index established by 20% of project duration rarely improves by more than 10%. A Cost Performance Index of 0.85 at month 2 of a 10-month project almost always finishes at 0.85 or below.
Cost Performance Index (CPI) and Schedule Performance Index (SPI) are the two core Earned Value Management metrics. Cost Performance Index = Earned Value ÷ Actual Cost. Earned Value is Budget at Completion multiplied by physical percentage complete. Actual Cost is what you have actually spent. A Cost Performance Index of 1.0 means every rupee spent has produced exactly one rupee of planned work. Above 1.0 = under budget. Below 1.0 = over budget.
Schedule Performance Index = Earned Value ÷ Planned Value. Planned Value is Budget at Completion multiplied by the percentage planned to be done per your baseline schedule today. A Schedule Performance Index of 1.0 = on schedule. Below 1.0 = behind schedule.
In Indian construction MSMEs, both indices are calculated at each Running Account bill cycle (monthly or fortnightly) using physically measured completion percentage — not billing or payment percentage, which lags real progress. The key PMBOK finding: Cost Performance Index established by 20% of project duration rarely changes by more than 10% in either direction — making it the earliest reliable overrun warning available.
Estimate at Completion (EAC) is the statistically expected total cost of the project if current cost performance continues. The most reliable formula for construction: Estimate at Completion = Budget at Completion ÷ Cost Performance Index.
Worked example (₹2 Cr office fit-out at month 5 of 8): Budget at Completion = ₹2 Cr. Physical complete = 62.5% (Earned Value = ₹1.25 Cr). Actual Cost to date = ₹1.34 Cr. Cost Performance Index = 1.25 ÷ 1.34 = 0.93. Estimate at Completion = 2.00 ÷ 0.93 = ₹2.15 Cr — ₹15 Lakh projected overrun.
Estimate to Complete = Estimate at Completion − Actual Cost = 2.15 − 1.34 = ₹81 Lakh still needed to finish. Variance at Completion = Budget at Completion − Estimate at Completion = −₹15 Lakh (negative = over budget). The EAC method based on Cost Performance Index is preferred over optimistic bottom-up re-estimates because it removes the human tendency to assume "we will recover in the next phase" — which Indian project data consistently shows does not happen.
A Schedule Performance Index below 1.0 in the first 10–15% of project duration is common and often recoverable — early ramp-up and mobilisation suppress Earned Value. The Liquidated Damages risk threshold is different: Schedule Performance Index below 0.90 sustained past 25–30% project completion.
Under CPWD GCC clause 2, Liquidated Damages at 1% per week (capped at 10% of contract value) begin accruing from the contractual completion date — not from when the Schedule Performance Index dips. But a Schedule Performance Index of 0.85 at 30% completion means the project is running approximately 15% behind schedule. On a 12-month CPWD project, that is 1.8 months of delay already built in — before any further issues.
Under FIDIC clause 8.7, Liquidated Damages are similarly calculated from the Time for Completion. The difference: FIDIC sub-clause 8.4 provides a genuine Extension of Time mechanism for employer-risk events (utility diversions, scope changes, force majeure) that must be claimed within 28 days under sub-clause 20.1. Tracking Schedule Performance Index monthly gives you the 28-day window — the only way to preserve the Extension of Time claim right.
VentureVitals AI calculates Cost Performance Index and Schedule Performance Index automatically from your Running Account bill data — no spreadsheet, no manual entry. 20-minute walkthrough. See it on your project.