By default our project check this option like below image so that when you update Duration % complete, P6 will update Actual units for you.

When you don’t want this happen, you can turn it off. However it will apply to the whole project.

How about you want to turn it off for only one activity.

There is another way to turn it off by go to the Resource dictionary and turn off for that resource.

However it will apply to all resource assignment in your project.

It’s impossible. You want to turn off for only 1 activity.

And I find out there is 1 solution.

The option “Recalculate Actual Units and Cost when duration % complete changes” doesn’t affect activity which is “Fix Units” or “Fix Units/time”.

So you can change the Duration type of that activity to “Fix Units” or “Fix Units/time”.

Now when you update Duration % complete, it doesn’t automatically update actual units.

We have 4 activities which have same calendar : Standard 5 day workweek. We use Total Float to calculate Critical path. The result is this:

When I change A1020 activity’s calendar to 1 Day Workweek. We use Total Float to calculate Critical path. The result is this:

You can see it’s wrong critical path.

Now when you choose Longest path option. It will become like this:

Now the critical path is better

So when you have multiple calendar project, consider to use Longest path option.

In my project, I receive updated data from construction team every month. However, they never update data correctly in that period.

For example, this month is December, most of activity they update start and finish within December but there are always some activities which is updated in November or even in October. (They said they forget to update those activities in November so now they update it this month).

In this case P6 will add some more units to November and make your November report wrong. You have sent November report to other parties and it can not be edited. So, the only solution is you move all November “mistake” unit to December.

You can use Excel to save figure of November and December. Then we can have Actual this month by taking December minus November.

However, we can do this right in Primavera.

First in November you need to run Tool -> Store period performance, to storage Actual Units (in fact this is the cumulative actual unit) to November period.

In December you just update as normal. Now you can show the “Actual This Period Units” column. And that’s the data we need.