How to Calculate Rolling Average Sales using DAX in Power BI

How to use DATESINPERIOD Function to Calculate the Rolling 12 Months Average Sales In Power BI
Lets suppose we have a Data Model as follows with Orders and Sales details.

From this Model, we can calculate the Rolling 12 Months Sales  and Average Sales using the below DAX Expressions.

Sales Rolling12M_Total =
VAR NumOfMonths=12
VAR LastSelectDate=MAX('tbl_Calendar'[cDate])

VAR PeriodRange=DATESINPERIOD('tbl_Calendar'[cDate], LastSelectDate,-NumOfMonths,MONTH)

VAR Result=CALCULATE(
                        SUMX(VALUES(tbl_Calendar[Month_No]), [Total Sales]), 

                            PeriodRange

                                )

VAR LastDateOfSales=MAX(tbl_OrderDetails[Order_Date])
VAR FirstSelectedDate=MIN('tbl_Calendar'[cDate])

RETURN
IF(FirstSelectedDate<=LastDateOfSales,Result)

Sales Rolling12M_Avg =
VAR NumOfMonths=12
VAR LastSelectDate=MAX('tbl_Calendar'[cDate])

VAR PeriodRange=DATESINPERIOD('tbl_Calendar'[cDate], LastSelectDate,-NumOfMonths,MONTH)

VAR Result=CALCULATE(
                        AVERAGEX(VALUES(tbl_Calendar[Month_No]), [Total Sales]), 

                            PeriodRange

                            )

VAR LastDateOfSales=MAX(tbl_OrderDetails[Order_Date])
VAR FirstSelectedDate=MIN('tbl_Calendar'[cDate])

RETURN
IF(FirstSelectedDate<=LastDateOfSales,Result)

Notes:

LastDateOfSales - is the last date for which the Sales is available

FirstSelectedDate - is the first visible date of each Selected Date/Month in the Visual.

The condition IF(FirstSelectedDate<=LastDateOfSales,Result) will ensures the result for only the available Sales dates.

Result :

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Thanks, TAMATAM ; Business Intelligence & Analytics Professional 

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