Long-duration projects and the fixed-rolling schedule
All projects start with a project baseline that includes the schedule, labor needs, and apportioned budget, with appropriate adjustments. Cost performance (CPI) and schedule performance (SPI) are appropriate monitoring indices, but frequently get misused with deleterious effects. Instead of using a frozen baseline, this article recommends keeping a rolling schedule window of six months or a year. For projects of long duration, the project management baseline schedule should be a high-level, roll-up schedule summary that establishes major project activities, milestones and deliverables but doesn't include a detailed work breakout. Likewise, the CPI and SPI should be measured against the roll-up level, and budgets should be reallocated in more detail with the rolling window.