The PMBOK talks about the PM’s “official” Estimate at Completion (EAC), which is determined by performing a detailed bottom-up estimate of the remaining work and adding costs incurred to-date. Fleming and Koppelman discuss three statistical methods of determining EAC. What is EAC? What is the significance of the three statistical methods of forecasting EAC? What is the difference between EAC and Budget at Completion (BAC)? Under what circumstances will they be equal?