A positive cost variance or a CPI greater than one indicates the project is under budget.

A negative cost variance or a CPI less than one indicates the project is over budget.

A CV of zero or a CPI of one indicates the project is on target. |

A positive schedule variance or a SPI greater than one indicates the project is ahead of schedule.

A negative schedule variance or a SPI less than one indicates the project is behind schedule.

An SV of zero or a SPI of one indicates the project is on target. |

For TCPI

Less than 1 is good. The farther below 1, the easier it will likely be to achieve the desired result.

At one: The same results are needed to achieve results.

Greater than one is not good. The farther above one, the more difficult it will be to achieve the desired result.

Analysis
Our project is doing quite well. It is estimated to come in at a cost of $833,333, which likely means spending another $213,333 to finish the project. This is $141,667 less than originally planned. This means it should be quite easy to meet senior-management goals as denoted in the original project plan.
4. Analysis * Schedule: The positive schedule variance and SPI above 1.0 indicates the project is ahead of schedule; however, the critical path for this project is A - C - E, and CP tasks are significantly behind schedule (SPI for A = 0.80). Be careful when analyzing project totals for SPI, as the critical path is not taken directly into consideration. * Budget: The project is currently significantly over budget (CPI = 0.78) by 27.5% where CV / EV = $ over budget = ($12,120 / $44,080) = 0.275. This is due to a severe over-budget situation in task A, which is 73.6% ($14,840 / $20,160 = 0.736) over cost. * The EAC indicates the project’s actual cost will exceed the budgeted amount by $34,260, or the project will be 35.5% over budget at completion when calculating using Option 1. * When the EAC is calculated using Option 2, the result is actually less than when using Option 1. This is because the size of task A and its poor performance compared to the other tasks is moderated when forecasted using the general project CPI.
Cost and Schedule Performance Index Thresholds
(Less than 1 = poor performance, greater than 1 = good performance) * 1.3 and up: investigate immediately * 1.2: Investigate at your leisure * 0.9 to 1.2: Generally okay * 0.9 to 0.8: Investigate * 0.8 to 0.6: Prompt review and action required * Less than 0.6: This project is in dire straits. Intervention by management may be needed to determine which actions should be taken as to the future of this project.
Variances and indexes are plotted on control charts for trend analysis.