What is To-Complete Performance Index (TCPI)?
TCPI is the efficiency the project must achieve on all remaining work to finish within a target budget — essentially, "how hard do we have to row from here?" Work remaining divided by funds remaining.
Its exam role is honesty: if a project's CPI is 0.83 but its TCPI is 1.12, someone is promising a dramatic turnaround. When TCPI drifts far above 1.0, the professional answer is usually to re-baseline through change control, not to hope.
Formula
TCPI = (BAC − EV) ÷ (BAC − AC)
Worked example
BAC = $100,000, EV = $35,000, AC = $42,000. TCPI = 65,000 ÷ 58,000 = 1.12 — the team must deliver $1.12 of value per remaining dollar to hit the original budget. Anything above ~1.10 is usually unrealistic.