# Re: Arithmetic sum of subtasks

Is it possble you can show an example of how to use the custom duration
field to calculate the sum ofsubtask durations ?

Thanks.

"Dale Howard [MVP]" wrote:

RakeshK --

What you are seeing in Microsoft Project is correct. The Duration of any
summary task is NOT the sum of the Durations of the subtasks. The Duration
of a summary task is calculated from the Start date of the earliest starting
task to the Finish date of the latest finishing task. But if you absolutely
need to calculate a custom Duration as the sum of the subtask Durations, you
would need to create a custom Duration field for this purpose. Hope this
helps.

--
Dale A. Howard [MVP]
VP of Educational Services
msProjectExperts
http://www.msprojectexperts.com
http://www.projectserverexperts.com
"We write the books on Project Server"

"RakeshK" <RakeshK@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:D54BC069-FA12-43A9-B7DF-C4D97C299432@xxxxxxxxxxxxxxxx
Hi,
Presently the duration of a summary task is NOT the arithmetic sum of the
durations of its subtasks. It is calculated as the difference between the
most end date and the least start date of the subtasks.

How can i show the arithmetic sum of duration of subtasks in a summary

.

## Relevant Pages

... The duration of a summary task is the time between when the earliest starting subtask begins and the latest finishing subtask ends. ... I have 1 task with 6 subtasks that are to be completed in 1 day. ... The WORK column has hours allotted to the 6 subs and totals correctly. ...
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• Re: calculate summary start and finish using pert anayst
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