Make Pie chart show percent rows of total rows

[JoeCrozier]

I have data that looks like this:

Its a row for every user in my clinical trials system, what their contact id is, and what department they're in.

I also have other data that is a row for every protocol we're tracking, one column of which is what department that protocol is in. 

I'd like to create a visual like this (pictured, though not working perfectly yet), where I select a study, it shows what department that study is in, and then a pie chart that would show:  "of the 821 total users, 328 of them are in that department"

It ALMOST works.  All the data is linked to each other, and if I select a different dept the pie chart will change to reflect the users in that department, the problem is it doesn't keep the 'out of 821' as a total.  The entire pie chart just becomes however many rows are in that department. 

How do I get the pie chart to show percent of total rows?

[v-yangliu-msft · Accepted solution]

Hi  @JoeCrozier ,

I created some data:

Here are the steps you can follow：

1. Create measure.

Measure =
var _select=SELECTCOLUMNS('Table',"1",[Department])
var _all=COUNTX(ALL('Table'),[User])
var _group=COUNTX(FILTER(ALL('Table'),'Table'[Department] in _select &&'Table'[Department]=MAX('Table'[Department])),[User])
return
DIVIDE(
    _group,_all)

2. Result:

Best Regards,

Liu Yang

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly