It is a date dim table. I can refresh it every day which is what I will do. I have a solution using a relative day field and then using if then statements but its not dymanic in the sense that I need to create a huge if then statment to go back the amount of time I want to. Which is fine but looking for something easier. Here is what I have done so far.
Calculated Column for Relative day
a Relative Day = datedim[DAY_IN_YEAR_NUM] - CALCULATE(SUM(datedim[DAY_IN_YEAR_NUM]),ALL(datedim),TODAY()=datedim[DATE_VALUE])