Performance Measurement Analysis and Forecasting

Value	Formula	Purpose
cost variance (CV)	EV - AC = CV	CV provides the cost performance of the project to help determine whether the project is proceeding as planned.
schedule variance (SV)	EV - PV = SV	SV indicates the project's schedule performance. This value can indicate whether the project work is proceeding as planned.
cost performance index (CPI)	EV / AC = CPI	For a cumulative CPI, divide the sum of all earned value (EV) budgets by the sum of all actual costs (ACs). A CPI of less than one indicates that the project is over budget, and a CPI of over one indicates that the project is coming in under the estimated budget.
schedule performance index (SPI)	EV / PV = SPI	Project managers can use the SPI to help predict when their projects will be completed. An SPI of one indicates the project is on schedule; greater than one indicates it is ahead of schedule; and less than one indicates it is behind schedule.
estimate at completion (EAC)	AC + ETC = EAC	EAC is used by project managers to give their best estimate of the total costs of projects based on actual costs to date. There are three formulas associated with this value. This formula is typically used when previous assumptions regarding costs are wrong.
estimate at completion (EAC)	AC + BAC – EV = EAC	Use this formula when variances are not expected to occur again. Budget at completion (BAC) is the total planned value (PV) at completion.
estimate at completion (EAC)	AC + ((BAC – EV) / CPI) = EAC	This formula is used to calculate the EAC when variances are likely to recur.
ETC	N/A	This ETC is not a calculated value based on any formula. Instead it is provided by the performing organization for use in the formula AC + ETC = EAC when previous cost estimates are wrong. The situations where atypical and typical variances are considered do not apply in this case.
estimate to complete (ETC)	BAC - EV = ETC	ETC can help project managers in forecasting what the final cost to finish the project may be. Two formulas are used to calculate this value. This formula is applied when variances are not expected to occur again.
estimate to complete (ETC)	(BAC - EV) / CPI = ETC	Use this formula to calculate the ETC for when variances are likely to recur.