Help with Linear Trend line ?

DL Validation Trend =

VAR Months =

    -- One row per month (MonthYear + numeric month order)

    SUMMARIZE (

        ALLSELECTED ( 'Date' ),

        'Date'[Year-Month Order],   -- numeric chronological key (YYYYMM)

        'Date'[MonthYear]           -- display label

    )

VAR Known =

    -- Add X and Y for regression

    ADDCOLUMNS (

        Months,

        "KnownX",

            RANKX (

                Months,

                'Date'[Year-Month Order],   -- sorting by monthly numeric key

                ,

                ASC

            ),

        "KnownY",

            CALCULATE ( [Drivers Licence Validation] )   -- monthly aggregated value

    )

VAR KnownFiltered =

    -- Remove empty months

    FILTER ( Known, NOT ISBLANK ( [KnownY] ) )

VAR SlopeIntercept =

    -- Linear regression over monthly points

    LINESTX ( KnownFiltered, [KnownY], [KnownX] )

VAR Slope =

    -- Regression slope (scalar)

    MAXX ( SlopeIntercept, [Slope1] )

VAR Intercept =

    -- Regression intercept (scalar)

    MAXX ( SlopeIntercept, [Intercept] )

VAR CurrentMonthOrder =

    -- The month currently in row context of the visual

    SELECTEDVALUE ( 'Date'[Year-Month Order] )

VAR CurrentX =

    -- Lookup the X-value (rank) for the current month

    MAXX (

        FILTER ( Known, 'Date'[Year-Month Order] = CurrentMonthOrder ),

        [KnownX]

    )

RETURN

    IF (

        ISBLANK ( CurrentMonthOrder ),

        BLANK (),

        Intercept + Slope * CurrentX   -- trend value for the current month

    )

Ther updated pbix is attached

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