What happens when the Cost Performance Index (CPI) is below 0.90?

When the Cost Performance Index (CPI) is below 0.90, it indicates that the project is not performing well in terms of budget management. Specifically, the CPI is a measure of cost efficiency and is calculated by dividing the earned value (EV) by the actual cost (AC). A CPI value below 1.0 suggests that the project is spending more money than planned for the work accomplished; when it is below 0.90, this implies substantially poor financial performance.

A CPI below 0.90 not only points to excessive spending but may also indicate misallocation of resources or underperformance in delivering project outputs within the allocated budget. Proper budget management entails ensuring that expenditures align closely with the value gained from project activities, and a CPI below this threshold demonstrates a clear discrepancy, signaling the need for corrective action to avoid overruns and potential project failure.

In contrast, this situation does not imply project efficiency, effective resource utilization, or confirm that the project is ahead of schedule, as those are typically associated with higher CPI values, indicating favorable financial health and performance.