Hello. I've heard that it is always best to create explicit function in powerpivot. An example is [2001 customers] = calculate([active customers], Sales[Year]= 2001)

Would I have to create one of those for each year instead of just filtering in the pivot table itself? The formula that builds off of that is [customer growth since 2001] = ([Active Customers]-[2001 Customers])/[2001 Customers])

It seems besides the point to have create this filtered equation JUST FOR 2001 year.