How to solve the missing workdays problem
The case of the missing workdays is a not-so-exotic situation that appears to bring up rather deep issues. It can happen in any situation where you change the context to calculate something other than what's available in the original context. In other words, whenever you use CALCULATE to change context, you may run into this problem without even noticing it. As filtering and context transformation is core to working with DAX, it is a fundamental issue. And as you may have guessed, it has everything to do with AutoExist.
The root of the problem
Let's take a very close look at the context in the last datapoint in May 2020's order intake chart. We haven't included all report elements in the image, but you can guess that there are a number of filters in this context:
'Calendar'[Year]: 2020'Calendar'[Month]: May'Calendar'[Workday in Month]: 21
What we would...
