Hello ! Thanks for this clear article. Unfortunately I have a strange behaviour : the relative function works for me but only of the previous data (date) is shown in my table/graph. Why is a no-sense. I'll try to be as clear as possible : To be able to use the "relative period" function, you will agree that you need the data of the previous period right, in addition to the current one ? Which means for example a montly value for 2017 and 2018 :

Date - Quantity
1/2017 43
2/2017 67
3/2017 67
...
1/2018 67
2/2018 54
etc...

The point is, when I create a relative period function, I don't want the 2017 date to be displayed in my graph or table, only the 2018 with NEXT to it, the relative n-1 field, which is what you explained perfectly and showed in your screenshots . So either I have 2017 data + 2018 AND relative n-1 fields showing up, OR, if I filter my table/graph to have only 2018 data, then the relative n-1 fields will be empty ! Really strange... Did I miss something? I'm using VA 7.4