Earned Value Management
Reviewed September 2026 · Civil Systems LLCYou can spend all the money and still not be ahead. Earned value is how you tell the difference.
Earned value compares completed work with the budget assigned to it. It helps you notice when spending and progress begin to separate, provided the team has a consistent way to measure completion.
PMI defines two core measures. Actual Cost (AC) is what you have spent. Earned Value (EV) is the budgeted value of the defined scope that has been completed.
The distinction matters. Actual cost records what the project spent. Earned value records how much planned value the completed work represents. A long week can raise actual cost without producing the progress shown in the schedule.
Each work package needs a measurement rule. A short task may earn value only when complete. Longer work may use weighted milestones, fixed formulas, or another objective method for recognizing partial progress. Logged hours alone are not earned value.
A simple representation of earned value against the cost of time.
How Value Is Earned
Each task or work package carries a planned budget and a method for measuring completion. This visual uses a simple 0/100 rule: a block earns its budgeted value when it is delivered. A real project may use weighted milestones or another defined method when partial completion needs to be recognized.
For example, assume a task was planned to cost $10,000 and to take one week. If it ultimately requires two weeks and costs $20,000, the project still earns $10,000 when the scope is completed (EV = $10,000; AC = $20,000). The additional spending does not increase value. It reduces performance.
Conversely, if the same $10,000 task is completed for $6,000, the earned value remains $10,000, but performance improves. Value is tied to completed scope against plan. Cost reflects what it took to achieve it.
CPI: The Performance Signal
Once value is separated from cost, the comparison becomes unavoidable. Earned Value reflects the budgeted value of completed scope; Actual Cost reflects what it took to complete it. The relationship between the two is captured in a single measure:
CPI = EV ÷ AC
A CPI above 1.0 indicates favorable cost performance. A CPI of exactly 1.0 is on plan. Below 1.0 indicates unfavorable cost performance.
The arithmetic is simple. The interpretation is not. CPI does not measure effort or intent. It measures alignment between plan and reality. If a $10,000 task ultimately costs $20,000, the earned value remains $10,000 and CPI drops to 0.50. If it costs $6,000, CPI rises above 1.0. In both cases, the scope earned is unchanged. Only performance shifts.
When CPI declines, something in the system has moved. Assumptions about scope, coordination, productivity, or timing are no longer holding. The plan and reality have begun to separate.
What to Check When CPI Falls
First check the inputs: has completed work been recorded consistently, and are the costs for the same reporting period? Then look for the work packages driving the change. An incorrect progress estimate calls for a different response than extra work or lower productivity.
Ask the team to estimate the remaining work, including review and corrections. Use that estimate to revisit the forecast. CPI is a prompt to investigate; it does not identify the cause or choose a recovery plan for you.
What counts as a good CPI?
A CPI above 1.0 is favorable cost performance, exactly 1.0 is on plan, and below 1.0 is unfavorable. Context still matters: the measurement method, data quality, trend, and remaining work affect what a manager should do next.
What's the difference between Actual Cost and Earned Value?
Actual Cost is what the project has spent. Earned Value is the budgeted value of work completed under the measurement method assigned to that work. One measures spend; the other measures planned value accomplished.
How do you calculate CPI?
CPI = EV ÷ AC. If completed work has an earned value of $10,000 and actual cost of $20,000, CPI is 0.50. If the same earned value costs $6,000, CPI is about 1.67.
Watch the signal change while you manage.
Critical Path lets cost and schedule performance respond to your decisions across the full project, not just one calculation.