How to count previous Quarter Data?

[Chdoula]

Hi Qlikers,

I have a question:

I have a table with 2 columns "Quarter" (format Q1 2019, Q2 2019...) & "Project code"

and I have a second table with "Project code" , "Project type" & "Project Result"

I have a stacked bar chart displaying as dimensions "Project type" & "Project Result" and as measure a count of "Project Results". I would like to copy the stacked bar chart and show the previous quarter versus current selection.

Which expression should I put as measure?

Thanks a lot in advance for your help and time