Help with Measure Calculation

[Edit] Sorry, this does something different... but I'll post the right solution in a moment. But try to understand this logic as well as it can be useful 🙂

// Assumptions:
// 1. There's a proper Dates table in the model (marked as a Date table in the model).
// 2. The main fact table is called FactTable.
// 3. Dates[Date] 1:* FactTable[Date]

[YTD YoY %] =
// Dates[Date] is of the datetime datatype without
// the time component. It's the primary key in 
// the Dates table.
var vLastDayWithData =
    CALCULATE(
        MAX( FactTable[Date] ),
        REMOVEFILTERS( )
    )
var vYtdPeriod =
    // This logic is needed in order to get
    // correct comparisons for periods that
    // have not yet finished.
    CALCULATETABLE(
        DATESYTD(
            Dates[Date]
        ),
        KEEPFILTERS(
            Dates[Date] <= vLastDayWithData 
        )
    )
var vYtdPeriodLastYear = SAMEPERIODLASTYEAR( vYtdPeriod )
var vYtdValue =
    CALCULATE(
        [Measure],
        vYtdPeriod
    )
var vYtdValueLastYear =
    CALCULATE(
        [Measure],
        vYtdPeriodLastYear
    )
var vChange =
    DIVIDE(
        vYtdValue - vYtdValueLastYear,
        vYtdValueLastYear
    )
return
    vChange