Once the CPI/SPI were calculated at some time-stamp, project manager should be deeper analyses, he need to predict the future cost:
ETC (Estimate To Completion)
Then EAC (Estimate At Completion) = AC + ETC
How to calculate ETC based on current situation (EV/AC/PV and SPI&CPI), there are usually three methods:
No matter which method PM chooses, as long as the calculated/predicted EAC is not acceptable, then it is an “early warning” to the team.
Even more, PM need calculate TCPI, the content below as copied from EVM on Wikipedia, it is very clear for me.
The To Complete Performance Index (TCPI) provides a projection of the anticipated performance required to achieve either the BAC or the EAC.
For the TCPI based on BAC (describing the performance required to meet the original BAC budgeted total):
or for the TCPI based on EAC (describing the performance required to meet a new, revised budget total EAC):
Independent estimate at completion (IEAC)
The IEAC is a metric to project total cost using the performance to date to project overall performance. This can be compared to the EAC, which is the manager’s projection.
Wish I success, again! +U!