S-Curve

Cumulative cost and schedule health at a glance.

SPI
CPI
Actual spend (AC)
Forecast final cost
Period 7 of 12

What you are looking at

Three lines carry the complete story. PV (purple) is planned value — the cumulative budget for work that should be done by each date. EV (green) is earned value — the budgeted cost of work actually completed. AC (red) is actual cost. The amber dashed line is the EAC forecast. Switch between cumulative cost, work completion and resource loading. The KPI cards show SPI, CPI, actual spend and projected final cost.

What most PMs miss

PMs show the S-curve but don't overlay all three lines — planned, actual and forecast together. Three lines are required, not one. Also: underspend in early phases looks good but almost always signals slow mobilisation, not efficiency. The forecast line (amber) is the one executives care about most — it translates the current trend into a final number.

The expert tip

Show the S-curve in every status report without being asked. Execs who see it unprompted trust you more — it signals you are tracking proactively, not reactively. Switch to the Behind schedule scenario to see exactly what a slow-start pattern looks like and how early you need to intervene to recover.