Variation between periods

Hi, edsonsouza 

Thanks for ExcelMonke reply. You can refer to his reply. If it does not work, I use Field Parameter to create two slicers, you can try following DAX.

DAX:

Changes =
VAR _choose_type =
    SELECTEDVALUE ( 'ChooseType'[Year/Month] )
// If choose single Year
VAR _currentYear =
    SELECTEDVALUE ( 'Date'[Year] )
VAR _currentYearSales =
    CALCULATE (
        SUM ( Sales[sales] ),
        YEAR ( Sales[Date] ) = _currentYear,
        ALL ( Sales )
    )
VAR _previousYear = _currentYear - 1
VAR _previousYearSales =
    CALCULATE (
        SUM ( Sales[sales] ),
        YEAR ( Sales[Date] ) = _previousYear,
        ALL ( Sales )
    )
// If choose Year and Month
// If choose single month
VAR _yearChanges =
    DIVIDE ( _currentYearSales - _previousYearSales, _previousYearSales )
VAR _year_Month =
    SELECTEDVALUE ( 'Date'[Year/Month] )
VAR _currentMonth =
    CALCULATE ( MAX ( 'Date'[Date] ), 'Date'[Year/Month] = _year_Month )
VAR _currentMonthSales =
    CALCULATE ( SUM ( Sales[sales] ), Sales[Date] = _currentMonth )
VAR _countRows =
    CALCULATE ( COUNTROWS ( Sales ) )
VAR _previousMonth =
    IF (
        NOT ISBLANK ( _countRows )
            && _countRows = 1,
        EOMONTH ( _currentMonth, -2 ) + 1
    )
VAR _previousMonthSales =
    CALCULATE ( SUM ( Sales[sales] ), Sales[Date] = _previousMonth )
VAR _singleMonthChanges =
    DIVIDE ( _currentMonthSales - _previousMonthSales, _previousMonthSales )

// If choose multiple months
VAR _minMultiMonths =
    CALCULATE ( MIN ( Sales[Date] ), ALLSELECTED ( 'Date'[Date] ) )
VAR _maxMultiMonths =
    CALCULATE ( MAX ( Sales[Date] ), ALLSELECTED ( 'Date'[Date] ) )
VAR _minSalesWhenMultiMonths =
    CALCULATE ( SUM ( Sales[sales] ), Sales[Date] = _minMultiMonths )
VAR _maxSalesWhenMultiMonths =
    CALCULATE ( SUM ( Sales[sales] ), Sales[Date] = _maxMultiMonths )
VAR _salesChangeMultiMonths =
    DIVIDE (
        _maxSalesWhenMultiMonths - _minSalesWhenMultiMonths,
        _minSalesWhenMultiMonths
    )
VAR _result =
    IF (
        _choose_type = "Year"
            && ISFILTERED ( 'Date'[Year] ),
        _yearChanges,
        IF (
            _choose_type = "Year/Month"
                && ISFILTERED ( 'Date'[Year/Month] )
                && _countRows = 1,
            _singleMonthChanges,
            IF (
                _choose_type = "Year/Month"
                    && ISFILTERED ( 'Date'[Year/Month] ),
                _salesChangeMultiMonths,
                "Please choose all slicers"
            )
        )
    )
RETURN
    _result

Best Regards,
Yang
Community Support Team

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