Copy matrix data into a new a new table

Dear PBi users,

I've managed to extract data from a very complicated sql database.

I've created the matrix i want, with the good kpis.

I want to study their variation in time, So i want to copy my matrix data into a new table with time indexation every month. Copying the entire tables from my request would make a huge file, as my matrix sums up a lot of rows.

Matrix from sql DB in april

Prjct    Kpi1 Kpi2

A          52    33

B           25    14

...

Every month or so, I want to indent my archive table as following :

Date        Prjct      Kpi1     Kpi2

04/2017   A           52        33

04/2017   B             25      14

...

05/2017   A           55       28

05/2017   B           20        18

...

And so on.

I used to copy my pivot table in excel in my "archive_table" "by hand". How can i reproduce this action?

Thanks in advance!