I am new to Qlik Sense and I want to create a comparison of customer sales for prior 12 months and current 12 months to see if they increased or decreased in purchases.
For example if customer A buys $1000 of widgets in prior 12 months (Jun 1 2016 - May 31 2017) and then buys $2000 more in current 12 months (Jun 1 2017 - May 31 2018) they had an increase of $1000. If customer A bought $1000 in prior 12 and $500 in current 12 there would be a -$500 decrease.
I can't include the current month (June 2018) in the calculations so last day end on May 31,2018.
Any help in building the formulas or set analysis would be greatly appreciated.
I have written this in SQL already, but I am trying to avoid using SQL views and use Qlik.