Schedule Analysis and Reporting
Analysis Techniques
Reporting begins with analysis. Know schedule variance analysis, critical path analysis, float analysis, and earned schedule. Earned schedule uses ES = time at which PV equals EV; SV(t) = ES − AT; SPI(t) = ES ÷ AT. Unlike SPI, SPI(t) is time-based and does not drift toward 1.0 at completion.
Forensic and Delay Analysis
Understand prospective vs. retrospective methods: impacted as-planned, as-built but-for, collapsed as-built, and window analysis. Window analysis divides the project into periods and attributes delay in each window - favored for contemporaneous analysis. Concurrent delay, pacing, and acceleration are concepts candidates must distinguish.
Reporting
Reports should be audience-appropriate: executive dashboards (milestones, SPI(t), CPI, float trends), working schedules (logic, float, constraints), and exception reports (negative float, open ends, missed milestones). Know the difference between a schedule narrative and a schedule report.
Worked Example
AT = 6 months, EV = 80, PV reaches 80 at month 5. ES = 5. SV(t) = 5 − 6 = −1 month; SPI(t) = 5 ÷ 6 = 0.83. The project is one month behind in time.
Traps
Using cost-based SPI to argue time performance; ignoring float consumption trends; and mixing prospective and retrospective methods in one analysis. Always state the data date and method used.
Rule of Thumb
If SPI is near 1.0 late in a project but milestones are slipping, check SPI(t) and float burn - cost-based SPI masks late schedule erosion.