Convert a table without date into a 6 Month (6 steps Moving Average

Hi Applicable88 

I know you want to calculate the 6 month rolling average of sum of percentages. And your Date column is not in date type.

Try my way to achieve your goal. I build a sample data model like yours to have a test.

Sample: 

Add a Rank column by dax, and we don't need to use date type column.

Rank = RANKX('Table','Table'[YearMonthKey],,ASC,Dense)

Measure:

Rolling 6 Avg = 
VAR _EndRank = MAX('Table'[Rank])
VAR _StartRank = _EndRank-6
VAR _Rolling6Sum = SUMX(FILTER(ALL('Table'),'Table'[Rank]<=_EndRank&&'Table'[Rank]>_StartRank),'Table'[Percentage])
VAR _Avg = DIVIDE(_Rolling6Sum,6)
Return
_Avg

Result is as below. Rolling 6 Avg in 202105 = 55,60%. 

Best Regards,

Rico Zhou

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