For Calculated Measures, Flow allows calculations to be configured based on a measure’s previous period’s value, or even a previous range of values.
When selecting a dependent measure in a measure calculation, select the “Properties” tab. Set the “Dependent” property to “Previous period” and the “Relative End” to -1.
Flow will now use the previous period of this measure in your calculation expression.
Set the “Dependent” property to “Previous range”, “Relative Start” to -30 and the “Relative End” to 0.
Flow will now use an array of values in your calculation expression. You will need to use this array in a Built-In or User Defined Function.
This Relative Range calculation is useful for “moving window” calculations (e.g. moving average, moving sum, etc.)