Earned value calculator
Earned value compares the budgeted value of work done with the plan and with what was spent. CPI is EV divided by AC, SPI is EV divided by PV, and the estimate at completion is the budget divided by CPI. An index below 1 means over cost or behind plan.
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The formulas the calculator applies
Earned value management uses four figures taken at the same cut-off date: the budget at completion (BAC), the planned value (PV) of the work scheduled to date, the earned value (EV) of the work actually done valued at its budgeted cost, and the actual cost (AC) spent so far. From them the calculator works out cost variance CV = EV - AC, schedule variance SV = EV - PV, the cost performance index CPI = EV / AC and the schedule performance index SPI = EV / PV.
The forecast then uses the estimate at completion EAC = BAC / CPI, the estimate to complete ETC = EAC - AC and the variance at completion VAC = BAC - EAC. Each result is followed by a plain-English reading, and a ratio that cannot be calculated is shown as undefined instead of a made-up number. A typed 0 stays 0.
Reading CPI and SPI
A CPI below 1 means each dirham spent has bought less than a dirham of budgeted work. A CPI above 1 means the opposite. An SPI below 1 means less work has been earned than was planned by this date, so the job is behind plan, and above 1 means it is ahead. Read the two together: a job can be on time but over cost, or under cost but late.
When actual cost is 0 the CPI is undefined, because nothing has been spent and efficiency cannot be measured. When planned value is 0 the SPI is undefined. When earned value is 0 but money has been spent, CPI is 0 and EAC = BAC / CPI has no answer. In all three cases the calculator says so.
Getting honest inputs from a contract
Earned value is the budget multiplied by the share of work really finished, so it is only as good as the progress measure behind it. Many contractors take it from the quantity surveyor's valuation or from the amount in the latest payment certificate. Use figures before VAT in all four boxes. Variations change the budget, so update BAC when a variation is agreed and keep the costing sheet in step.
SupaJack Construct shows each project's contract value, costing sheet and cost so far together on the money tab of projects and tenders, which supplies BAC and AC. It has no programme or scheduling module, as this answer explains, so planned value comes from your own programme. See the tendering and costing guide and the interim payments guide.
Related calculators
To turn progress into cash use the payment certificate calculator, the retention calculator, the advance payment recovery calculator and the VAT calculator. The interim payments and finance and VAT pages show where those figures land in the ledger.
Worked example
The table uses a AED 1,200,000 job at a mid-point review.
| Result | Working | Value |
|---|---|---|
| Cost variance | 450,000 - 540,000 | -90,000.00 |
| Schedule variance | 450,000 - 500,000 | -50,000.00 |
| CPI | 450,000 / 540,000 | 0.83 |
| SPI | 450,000 / 500,000 | 0.90 |
| EAC | 1,200,000 / 0.8333 | 1,440,000.00 |
| ETC | 1,440,000 - 540,000 | 900,000.00 |
| VAC | 1,200,000 - 1,440,000 | -240,000.00 |
Worked example
With a budget of AED 1,200,000, planned value 500,000, earned value 450,000 and actual cost 540,000, cost variance is 450,000 - 540,000 = -90,000 and schedule variance is 450,000 - 500,000 = -50,000. CPI is 450,000 / 540,000 = 0.83 and SPI is 0.90. If the cost efficiency continues, EAC is 1,200,000 / 0.8333 = AED 1,440,000, so AED 900,000 is still to spend and the job finishes AED 240,000 over budget.
Questions people ask
What is earned value?
The budgeted cost of the work actually completed at a given date, used to compare progress and cost against the plan.
What is a good CPI?
A CPI of 1 or more means the work is costing no more than budgeted. Below 1 means it is costing more.
What does an SPI below 1 mean?
Less work has been earned than was planned by the cut-off date, so the job is behind plan.
Why does the calculator say CPI is undefined?
CPI divides by actual cost. If actual cost is 0 there is nothing to divide by, and showing a default would mislead.
Is EAC = BAC / CPI the only forecast?
No. It assumes the cost efficiency so far continues. If the overrun was a one-off, AC + (BAC - EV) is another common forecast.
What is BAC?
The total budget for the scope, including approved variations, before any contingency you hold outside the budget.
How do I measure earned value?
Multiply the budget of each item by its percentage complete, or use the quantity surveyor's valuation of work done.
Does it forecast the finish date?
No. SPI shows whether the job is ahead or behind, but the finish date needs your programme.
Should the figures include VAT?
Use figures before VAT in all four boxes so the ratios compare like with like.
Does SupaJack Construct produce earned value reports?
This calculator does the arithmetic. The contract value and cost so far come from the project money tab, and planned value from your own programme.