# Calculate and explain earned value (CPI, SPI, and EAC)

Works out earned value metrics from your figures and explains in plain words what they say about cost and schedule.

- Topic: Data & Analysis
- Framework: RTF
- Level: Standard
- Tags: Finance, Explain & Teach, Fill-in Template
- Source: https://www.thinkwithprompt.com/prompts/calculate-and-explain-earned-value-cpi-spi-and-eac

## Prompt

```text
Help me calculate earned value metrics for my project and explain what they mean.

**Budget at completion (BAC):** [TOTAL approved budget]
**Planned value (PV) to date:** [budgeted cost of work scheduled to date]
**Earned value (EV) to date:** [budgeted cost of work actually completed - or give me % complete per work package and its budget]
**Actual cost (AC) to date:** [what we have actually spent]
**Reporting date and planned end date:** [DATES]
**Context:** [known reasons for over- or under-spend, upcoming big costs, changes approved]

Calculate and show the formula for each:
- Cost variance (CV = EV - AC) and schedule variance (SV = EV - PV).
- CPI (EV / AC) and SPI (EV / PV).
- Estimate at completion using two methods: EAC = BAC / CPI (current performance continues) and EAC = AC + (BAC - EV) (remaining work goes to plan).
- Estimate to complete (ETC) and variance at completion (VAC).
- TCPI - the efficiency needed on remaining work to finish on budget.

Rules: use only my numbers; do not fill in missing values. Point out if "% complete" looks like a guess, since it drives everything. Note that SPI drifts toward 1.0 near the end of a project and becomes less useful.

Return:
1. A results table with each metric, value, and a one-line meaning.
2. A plain-English summary for a non-finance sponsor (under 120 words).
3. Which EAC method is more realistic here, and why.
4. 3 actions the numbers suggest.
```

## What to fill in

- TOTAL approved budget
- budgeted cost of work scheduled to date
- what we have actually spent
- DATES

Free to copy and use. From ThinkWithPrompt (https://www.thinkwithprompt.com/), a library of 2,663 curated AI prompts.