Why when the value of a pie chart is blank, the pie chart still show something?

[Yutong]

I want to show a dynamic chart according to how many years were chosen in a slicer. When 1 years was selected, the pie chart would show, otherwise the pie chart would show nothing. So I create a measure as the value of the pie chart.

stay number= if(COUNTROWS(VALUES(table1[years])=1,DISTINCTCOUNT(table1[Stay Number]),BLANK()).

The problem is that the pie chart still show some data when this measure return BLANK().  I am so confused cause when I let stay number directly equals BLANK(), the pie chart works correctly. I wonder if there's sth wrong with this DAX, but I've checked the DAX indeed return BLANK() when I selected 2 years.

I also try another measure:

stay number = if(ISFILTERED(table1[years]),DISTINCTCOUNT(table1[Stay Number]),BLANK()).

The pie chart with this measure works correctly all the time. But it does not satisfy my requirement: only show when 1 fiscal year was selected.

How can I solve it?

[Ritaf1983]

Hi @Yutong 

Please provide sample data that covers your issue or question completely, in a usable format (not as a screenshot).
https://community.powerbi.com/t5/Community-Blog/How-to-provide-sample-data-in-the-Power-BI-Forum/ba-...
Please show the expected outcome based on the sample data you provided.

https://community.powerbi.com/t5/Desktop/How-to-Get-Your-Question-Answered-Quickly/m-p/1447523