SSAS Date Utility Dimensions: Pre-Aggregating Over Time

A pretty common question in business intelligence (and within SSAS cubes specifically) is numbers at points in time. How does my performance from this month compare to last month? How about this month last year? What is the actual difference? Luckily, there is a great way that we can easily build this out and give this functionality to business users, without having to create huge, complex MDX scripts. It involves creating a date utility dimensions, bringing it into the SSAS database, and then writing a simple MDX script. To start, create a date calculation dimension table in your data warehouse (or wherever your date dimension is):