Project Management Formulas Quick Reference

PM Formulas Quick Reference

Interactive calculators for essential project management formulas

Schedule Variance (SV)
Measures schedule performance compared to plan
SV = EV – PV

Where: EV = Earned Value, PV = Planned Value

Positive values indicate ahead of schedule, negative values indicate behind schedule.

Calculate Schedule Variance
Example
Project at week 10:
EV = $50,000 (work completed)
PV = $45,000 (work planned)
SV = $50,000 – $45,000 = $5,000
Result: $5,000 ahead of schedule
Cost Variance (CV)
Measures cost performance compared to budget
CV = EV – AC

Where: EV = Earned Value, AC = Actual Cost

Positive values indicate under budget, negative values indicate over budget.

Calculate Cost Variance
Schedule Performance Index (SPI)
Efficiency of schedule performance
SPI = EV / PV

Where: EV = Earned Value, PV = Planned Value

Values > 1.0 indicate ahead of schedule, < 1.0 indicate behind schedule.

Calculate Schedule Performance Index
Cost Performance Index (CPI)
Efficiency of cost performance
CPI = EV / AC

Where: EV = Earned Value, AC = Actual Cost

Values > 1.0 indicate under budget, < 1.0 indicate over budget.

Calculate Cost Performance Index
Estimate at Completion (EAC)
Forecasted total project cost
EAC = BAC / CPI

Where: BAC = Budget at Completion, CPI = Cost Performance Index

Forecasts total project cost based on current performance.

Calculate Estimate at Completion
Float (Slack) Calculation
Available schedule flexibility
Float = LS – ES or LF – EF

Where: LS = Late Start, ES = Early Start, LF = Late Finish, EF = Early Finish

Zero float indicates activities on the critical path.

Calculate Float
Defect Density
Quality measurement per unit
Defect Density = Total Defects / Size

Where: Total Defects = Number of defects found, Size = Lines of code, pages, etc.

Lower values indicate better quality.

Calculate Defect Density
Return on Investment (ROI)
Financial benefit measurement
ROI = (Gain – Cost) / Cost × 100%

Where: Gain = Financial benefit, Cost = Investment cost

Higher percentages indicate better financial returns.

Calculate ROI