Project data
One row per period: period, planned value (PV), earned value (EV), actual cost (AC). Leave EV and AC blank for future periods — the forecast uses the last period that has all three.
Position at data date
- CPI cost
- —
- SPI schedule
- —
- Cost variance
- —
- Schedule variance
- —
- EAC forecast final
- —
- VAC over/under
- —
- ETC still to spend
- —
- TCPI to hit BAC
- —
S-curves
Planned, earned and actual cumulative value with the EAC trajectoryPeriod detail
| Period | PV | EV | AC | CPI | SPI | CV | SV |
|---|
Method and limits
Standard earned value arithmetic: CV = EV − AC, SV = EV − PV, CPI = EV/AC, SPI = EV/PV. The forecast uses the cumulative-CPI method, EAC = BAC / CPI, with ETC = EAC − AC, VAC = BAC − EAC and TCPI = (BAC − EV) / (BAC − AC).
EAC by cumulative CPI assumes past cost performance continues to the end. That is the most defensible default and the one most owners expect, but it is pessimistic on projects whose early periods carried mobilisation inefficiency, and optimistic where the hard scope is still ahead. PMI recognises three other EAC formulas — budget-rate, SPI-weighted, and bottom-up — which can differ by 10% or more on the same data; where the number drives a claim, state which formula produced it.
SPI is a cost-based proxy for schedule and goes to 1.0 at completion however late the project finishes, so it is unreliable in the final third. Earned schedule, or the critical path itself, is the right measure there. None of this is a substitute for a CPM analysis: EVM tells you the magnitude of a problem, not which activities caused it.
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