Your most recent project performance report indicates that your cumulative Schedule Performance ...

Key concepts to be covered in the response could include, but are not limited to:

The schedule performance index (SPI) is a measure of schedule efficiency expressed as the ration of EV to PV. The SPI of .85 demonstrates that our project is proceeding less efficiently than planned and is behind schedule.

The cost performance index (CPI) is a measure of cost efficiency of budgeted resources, expressed as the ratio of EV to AC. The CPI of .90 demonstrates that our project is over budget, and that we are only receiving 0.90 worth of results for every dollar we have spent.

Given this information, we can also calculate the Estimate to Complete (ETC) and the Estimate at Completion (EAC), which are the expected cost needed to finish all the remaining project work, and the expected cost of completing all work.