Filtering Dates

Hi All,

I am trying to do the following in the Activity History Design Analysis:

Rep Name     Overdue     90 day     180 Day     >180

Bret                    16               25            0               56

I cannot for the life of me figure out how to get the dates to filter. I see references to TIMESTAMPADD and SQL_TSI_MONTH but I can;t make heads or tails of it.

Overdue should be anything less than current date

90 day should be anything >= current date and < 91 days from current date

180 day should be anything >= 91 days from current date and < 180 days from current date

>180 should be anything > 180 days from current date

Can someone please help me out with this.