today I will show you how % Complete is calculate on Summary Task level, and on Project Level as well, using Microsoft Project for the Web!
First, I will create one simple Project:
Firs three Tasks are connected, and second three Tasks are not connected at all. Now I will say that Task 1, and Task 6 are 100% completed:
As you can see, Summary 1 is marked as 50% completed. The calculation is simple: Task 1 has 3 days Duration. All Tasks under this Summary Tasks has 6 days duration (Task 1 = 3 days, Task 2 = 2 days, and Task 3 = 1 day, so Total 6 days). Now, 3 days (Task 1) / 6 Days (Total) = 50%
Similar, Summary 2 is marked as 17% completed. The calculation is simple: Task 6 ha 1 day Duration. All Tasks under this Summary Tasks has 6 days duration (Task 4 = 3 days, Task 5 = 2 days, and Task 6 = 1 day, so Total 6 days). Now, 1 day (Task 6) / 6 Days (Total) = 17%
Now I will click on My Project, and I will see:
Project % complete is 33%. Total Duration of all Tasks is 12 days! Now, Task 1 + Task 6 = 4 days duration. And, then Calculation is simple 4/12 = 33%.
Be aware of Milestone! It has 0 days and it brings 1 %! I will mark all Tasks as 100% completed, except the Milestone:
As you can see, If you do not mark all milestones 100% completed, even when all other Tasks are marked as completed, Summary Tasks, and Project as a whole remains 99% finished, and you do not want that.