Calculator
CPI project management calculator — earned value, Malaysia
Four inputs — budget, actual cost, how much work is done, how much should have been done — and you get CPI, SPI, both variances, and a forecast of where the project lands.
Earned value (EV)
BAC × % complete
RM200,000
Planned value (PV)
BAC × % planned
RM250,000
Cost performance index (CPI)
EV ÷ AC — you are over budget
0.87
Schedule performance index (SPI)
EV ÷ PV — you are behind schedule
0.80
Cost variance (CV)
EV − AC
RM-30,000
Schedule variance (SV)
EV − PV
RM-50,000
Estimate at completion (EAC)
BAC ÷ CPI
RM575,000
Estimate to complete (ETC)
EAC − AC
RM345,000
Variance at completion (VAC)
BAC − EAC
RM-75,000
To-complete performance index (TCPI)
(BAC − EV) ÷ (BAC − AC)
1.11
EAC here uses BAC ÷ CPI, which assumes the cost performance you have seen so far continues. That is the most commonly used formula and it is not the only accepted one — where past variance was a one-off, EAC = AC + (BAC − EV) is the better fit. Currency is cosmetic; the indices are ratios and work in any currency.
Reading the two indices
CPI is earned value divided by actual cost. Above 1.0 you are getting more than a ringgit of work per ringgit spent; below 1.0 you are getting less. A CPI of 0.85 means you are spending RM1.00 to deliver 85 sen of work.
SPI is earned value divided by planned value. Above 1.0 you are ahead of the plan, below it you are behind — in value terms rather than in days, which is why SPI can read 1.0 on a project that is still going to miss its date.
The pair together is more useful than either alone. Good CPI with poor SPI usually means work is efficient but under-resourced. Poor CPI with good SPI often means the schedule is being bought with overtime, and it tends to be the more dangerous of the two because it looks fine on a milestone report.
The one number most worth watching is the trend rather than the value. A CPI that has fallen from 0.98 to 0.91 over three reporting periods is telling you something a single reading cannot.
The honest caveat about earned value
Everything here depends on the percentage complete being honest, and that figure is the softest number in project management. Where it is self-reported by the person doing the work, with no objective completion criteria, earned value inherits the optimism and then presents it with two decimal places.
The fix is not a better formula. It is defining, before work starts, what done means for each deliverable and who signs it off — which is a scoping discipline rather than a reporting one.
Questions
›What is a good CPI?
Anything at or above 1.0 means you are delivering at or under the budgeted rate. Below 1.0 means each unit of work is costing more than planned.
Context matters more than the threshold: a CPI of 0.95 on a project with generous contingency is a different situation from 0.95 on one with none.
›Which EAC formula does this use?
BAC divided by CPI, which assumes the cost performance seen so far continues for the rest of the project. It is the most commonly used version.
It is not the only accepted one. Where the overspend was a one-off that will not repeat, EAC = AC + (BAC − EV) is the better fit and will give a lower forecast.
›What does TCPI tell me?
The cost efficiency you would have to achieve on all remaining work to finish exactly on budget.
It is most useful as a reality check. If your CPI to date is 0.85 and TCPI says you now need 1.25, the budget conversation is overdue.
›Do I need earned value on a small project?
Rarely in full. The overhead of measuring percentage complete properly is only worth it when the project is long enough for a trend to mean something.
On a short project the same instinct is better served by a weekly look at what was finished against what was promised.
Get a scoped quote
Tell us your team size, timeframe and whether you pay the HRD Corp levy. Within one working day you get a day rate, a suggested course shape and how to claim it through HRD Corp.