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MS Project Calculating Duration Incorrectly
When I set a fixed duration task to start on 5/25 and finish on 6/7, this is a duration of 10 days. MS Project for some reason however, is displaying a duration of 12 days. This is incorrect. I don't' understand why its doing this. If I manually change the duration field to 10 days, then project changes the finish date to 6/6, which is still not correct because working days from 5/25 to 6/6 would be 8 days. I have May 30th scheduled as a non-working day for memorial day. See screenshot. I'm not sure if it has anything to do with the options I have set for the project which is 6 hours per day, 30 hours per week to account for the reality that its not realistic for someone to be able to dedicate a full 8 hour day to project work.
- John Bacon,
I'm guessing you did not change the working calendar to reflect the 6 hour work day. By default, each work day is 8 hours (8:00 AM to 12:00 PM and 1:00 PM to 5:00 PM). The number of default days from 5/25/22 through 6/7/22, including the non-working memorial day, is 9. So 9 of the default 8 hour working days equals 72 hours. However, you have re-defined a "day" as 6 hours so 72 divided by 6 equals, wait for it, 12 "days".
The fact that resources may only be 75% efficient is not relevant for Project's scheduling calculation. That's something you will have to take into account when you estimate task durations and assign resources.
Hope this helps.
John
- John Bacon,
I'm guessing you did not change the working calendar to reflect the 6 hour work day. By default, each work day is 8 hours (8:00 AM to 12:00 PM and 1:00 PM to 5:00 PM). The number of default days from 5/25/22 through 6/7/22, including the non-working memorial day, is 9. So 9 of the default 8 hour working days equals 72 hours. However, you have re-defined a "day" as 6 hours so 72 divided by 6 equals, wait for it, 12 "days".
The fact that resources may only be 75% efficient is not relevant for Project's scheduling calculation. That's something you will have to take into account when you estimate task durations and assign resources.
Hope this helps.
John- Yes. I checked and I did leave the project calendar work times from 8-12 and 1-5. I thought by changing working hours in project schedule options to 6, project would do its calculations accordingly assuming a resource assigned at 100% is still only 6 hours per day. So what you are suggesting is that I change the working hours per day back to 8, hours per week back to 40. Leave the project calendar working time as 8-12 and 1-5, but add resources with Max Units of 75% to account for administrative non-project related tasks performed during the day, and this should fix my calculation issue?
Or, if I just change the project calendar working times to 8-12 and 1-3. Will that also resolve my duration, start date, finish date discrepancy?
