Dynamic Rate calculation in Last 12 month expression

[aniketsr]

Hi All,

We have a dynamic rate populated from a table as mentioned in the excel

The LTM logic is as mentioned below :

Sum({$< intYearMonth,Year,Month,intYearMonth={'>$(=(Max(intYearMonth)-100))  <=$(=(Max(intYearMonth)))'}>} Sales)

Please guide me with a solution on how we can bifurcate the rate if the year changes:

viz- if the max Intyearmonth is 201807 then the last 12 month calculation will go to 201708, but the rate of 2018 is different from that of 2017

attached is the data in excel fort reference