Getting a rolling average should be an native function in Power BI. However maybe at the time you read this, there will already be a a feature added. However, in the meantime lets dive into dynamic rolling average using Power BI.
Here are the list of functions will be using the to create our calculation:
- SUM
- CALCULATE
- LASTDATE
- DATESINPERIOD
- DISTINCTCOUNT
There are two points to this formula:
- Calculating the sum of the value in the period
- Calculating the count of days in the period
- Dividing these two calculations
Calculating the Sum during the period
CALCULATE(SUM(VALUE), DATESINPERIOD(DATE,START DATE, NUMBER OF INTERVALS, INTERVAL)
Calculating the count of day in the period
CALCULATE(DISTINCTCOUNT(DATE), DATESINPERIOD(DATE,START DATE, NUMBER OF INTERVALS, INTERVAL)
Formula for a 28 day average
To make this much cleaner you can use variables that will allow achieve the same affect.
Dynamic Power BI Rolling Average with DAX Parameters
