During the final iteration of the execution phase, the project has a cost performanceindex (CP!)...

The Cost Performance Index (CPI) of 0.9 indicates that the project is over budget. This means that for every dollar invested, only 90 cents of value is being earned. The Schedule Performance Index (SPI) of 1.0 indicates that the project is on schedule. Therefore, to avoid a budget shortfall, the project manager should look for cost-saving opportunities. This could involve identifying and eliminating unnecessary costs, negotiating better deals with suppliers, or finding more efficient ways to complete tasks. References: PMBOK Guide, 6th Edition, Section 7.4.2.3, “Cost Forecasts” and Section 7.2.2.4, “Cost Management Plan”