An S-curve shows cumulative work over time. Its shape comes from how each activity's hours are spread across its own working days. If that spread is wrong, the curve can look fine and still mislead the people staffing the job.
What makes a curve reliable
- Spread each assignment over the working time of the activity's own calendar. A six-day activity and a five-day activity do not burn hours alike.
- Split actuals from remaining at the data date, so history stops moving.
- Count labor resources only for manhours. Nonlabor and material belong in the cost view.
- Reconcile the total back to the schedule. A curve that does not add up to the file is not a curve you can present.
Early, late and planned
The early curve shows the work if everything starts as soon as logic allows. The late curve shows the last moment. The space between them is your float shown as manhours. Planned shows the budget over the planned dates, and is the line to measure against.
From hours to people
FTE is period hours divided by the hours one person works in that period. That second number has to be yours, because it depends on your shifts. As a worked example only: 800 hours in a week, at 40 hours per person, is 20 people. If the site cannot physically hold 20 people in that area, the schedule has a problem no float number will show you.
Build these curves from your XERIs your own schedule healthy?
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