### Mind Square Brackets in one of the Estimate at Completion (EAC) formulas!

When calculating Estimate at Completion or in short 'EAC', in a scenario when things are not quite going to plan but you still DO need to stick to a deadline, you need to consider both CPI and SPI. In this case take note of the square brackets (or [...]) in the formula. This is the only instance (among the 50 or so other formulas you will need to know for the exam) where you officially need to apply square brackets.

It's one of the more complicated formulas but don't worry. It's not that difficult.

The formula is:

$$$EAC=AC+\Bigg[\frac{(BAC - EV)}{(CPI * SPI)}\Bigg]$$$
where
EAC ... Estimate at Completion
BAC ... Budget at Completion, or 'total budget' or in layman's terms money put aside for the whole project. Often calculated as sum of all Planned Values (PV)
EV ... Earned Value, or simply, what you have done so far (more precicely how much money you have earned on the project so far)
SPI ... Schedule Performance Index

CPI ... Cost Performance Index