How to sum time ranges

I have a problem when aggregating lineitem by time .

 

I want to aggregate Amount by "Aggregate Lineitem" (From Jan-21 To Mar-21).

The Module A&B has set by time range, so we can't do it.

 

Table A ( Time Range : past 2years)

ListMonthJan-21Feb-21Mar-21Apr-21May-21
LineitemAmount A100200300400500
 Aggregate  
 Amount B10020030000

 

Table B (No Applies To) 

ListNone 
LineitemAmount600

 

 

Please give me a solution.

Answers