How to compare different time periods in one table

[Anonymous]

I'm having trouble coming up with a method to do something like this:

Type	Sales
1	Sum(Sales) where Sale Date is in a range dependant on dimension value (Fields StartDate and EndDate)
2	Sum(Sales) where Sale Date is in a range dependant on dimension value (Fields StartDate and EndDate)

Where each Type has a StartDate and EndDate.

for example for Type = 1, Sales between StartDate = 10/1/2015 and EndDate = 10/31/2015

and for             Type = 2, Sales between StartDate = 10/15/2015 and EndDate = 11/5/2015

The number of distinct Types is dynamic. I've never used alternate states but could that be used for this?

[Gysbert_Wassenaar]

Add StartDate and EndDate as dimensions and use Sum(Sales) as expression.