The Performance Index option displays schedule performance index (SPI), cost performance index (CPI), and to complete performance index (TCPI) calculations. Performance index values are calculated as follows.
Schedule performance index (SPI)
Earned Value of Cost or Quantity / Planned Value of Cost or Quantity
A measure of the work accomplished as a percentage of the work scheduled, SPI indicates whether you are meeting earned and planned values within your schedule. You can set performance thresholds for SPI calculated values to determine whether you need to take corrective action.
Cost performance index (CPI)
Earned Value of Cost or Quantity / Cost or Quantity to Date
A measure of the value of work accomplished as a percentage of the actual costs, CPI indicates whether you have spent money over the budget to date. You can set performance thresholds for CPI calculated values to determine whether you need to take corrective action.
To complete performance index (TCPI)
Budget Earned Value / Estimate to Complete
A measure of the value of the project work that is remaining, TCPI enables the project manager to determine the level of performance needed to achieve the cost or time objectives. You can set performance thresholds for TCPI calculated values to determine whether you need to take corrective action.