There are 3 Activity Percent Complete types in Primavera P6.
Duration Percent Complete: This is the most commonly used type and is the default setting. This type is used to calculate an activity’s percent complete (progress) based on original and remaining durations.
This is used in activities where percent complete is not measurable and is generally specified based on duration, e.g. Level of Effort activities.
Activity % Complete = (Original Duration – Remaining Duration) / (Original Duration)
For example, if an activity with 10 days Original Duration (OD) is updated to show that now it has a Remaining Duration (RD) of 8 days, then its percent complete = (10 – 8) / 10 = 20%.
Alternatively, the percent complete may directly be specified and P6 will calculate the RD based on the above formula.
Physical Percent Complete: This type represents the actual work accomplished for the activity and is used when quantifiable deliverables are involved. In this case, the actual work done, the remaining duration and the percent complete are all specifically entered.
Units Percent Complete: This type is used when resources are assigned and progress is based on actual units performed.
Similar to Physical Percent Complete, the RD should be adjusted manually.