The data date is the last date you recorded progress in the form of actual dates, percent of work completed, revised remaining duration, or actual quantities or costs.

P3e schedules activities from the project data date, using the project start date as the initial data date.

Be sure to change the data date and reschedule a project each time you record progress for activities. For example, suppose you update the schedule every Friday and the current data date is Friday, November 5. When one week elapses and it is November 12, update progress through the end of the day November 11, then advance the data date to November 12. P3e revises the schedule based on the actual dates, delays, and other changes you recorded during the past week.

Always assume that the data date starts the workperiod; the data date can be the beginning of the hour, day, week, or month. P3e does not credit work accomplished on the data date because it is the beginning of the period.

During the project, the data date moves forward toward the project completion date. The actual dates can serve as historical data for planning another project.