Skip to content

EVM Cost and Schedule Variance Visualization

Run the EVM Variance MicroSim Fullscreen

About This MicroSim

Earned Value Management (EVM) is the closest thing project managers have to a vital-signs monitor. From three numbers — Planned Value, Earned Value, and Actual Cost — five derived metrics fall out, and from those metrics you can diagnose whether a project is behind, over, both, or neither.

This MicroSim plots all three curves over a 12-month project and lets you slide a cursor along the timeline. The side panel computes CV, SV, CPI, SPI, and EAC live as you move the cursor, color-coding each metric green or magenta depending on whether it's healthy.

Three preset scenarios let you see how the metrics behave under different project-health states:

  • Behind Schedule, Under Budget — the most common pattern: cheap and slow
  • Ahead of Schedule, Under Budget — the rarest and best
  • On Schedule, Over Budget — fast and expensive

How to Use

  1. Pick a scenario with the buttons at the top
  2. Slide the cursor to any month; metrics update instantly
  3. Watch the EAC — when CPI < 1, EAC blows past BAC and goes red

The Five Metrics at a Glance

Metric Formula Healthy when
CV Cost Variance EV − AC ≥ 0
SV Schedule Variance EV − PV ≥ 0
CPI Cost Performance Index EV ÷ AC ≥ 1.0
SPI Schedule Performance Index EV ÷ PV ≥ 1.0
EAC Estimate at Completion BAC ÷ CPI ≤ BAC

Embedding This MicroSim

<iframe src="https://dmccreary.github.io/information-systems/sims/evm-variance-visualization/main.html"
        height="722px" width="100%" scrolling="no"></iframe>

Lesson Plan

Learning Objectives

By the end of this activity, students will be able to:

  1. Compute CV, SV, CPI, SPI, and EAC from PV, EV, and AC
  2. Interpret what each metric says about project health
  3. Diagnose project status from the visual relationship of the three curves
  4. Forecast final cost (EAC) given current performance trend

Suggested Activities

  1. Three-Curve Reading (5 min) — Show one scenario without the metrics panel. Have students sketch where they think CPI and SPI sit before revealing.
  2. Scenario Diagnosis (10 min) — For each of the three preset scenarios, write a one-sentence executive summary of project health.
  3. EAC Forecast (10 min) — At month 6 of the "Behind, Under" scenario, will the project finish under or over budget? Justify with the numbers.
  4. Status Report Drill (15 min) — Pick any month + scenario. Write a 100-word status update for a steering committee.

Assessment

  • Compute all five metrics given a stated PV, EV, AC
  • Match a project narrative ("we're cheap but late") to its EVM signature
  • Explain to a non-technical stakeholder why CPI < 1 is a worse sign than SV < 0

References

  • PMI (2021). A Guide to the Project Management Body of Knowledge (PMBOK Guide), 7th ed.
  • Fleming, Q. & Koppelman, J. (2010). Earned Value Project Management, 4th ed.