Power BI趋势图展示最近N月度量值

参考度量值

Sales_Per_Month = 
//计算当年各个月的sales
VAR Max_Month =
    SELECTEDVALUE ( 'Dim_Calendar'[Calendar Month Num] )
RETURN
    CALCULATE (
        [Amt_Vol_Sales_Base],
        DATESINPERIOD (
            'Dim_Calendar'[Date],
            MAX ( 'Dim_Calendar'[Date] ),
            - Max_Month,
            MONTH
        )
    )