latest non blank values

[NILU090]

Hi Team,Please find the datamodel and output that i require.
I want show difference between current value and last non blank value.

I tried NONBLANKVALUE, howeve its not working. 

please help me on this.

[johnt75]

Try

Diff with previous =
VAR CurrentDate =
    MAX ( 'Date'[Date] )
VAR CurrentValue =
    SELECTEDVALUE ( 'Fact'[Value] )
VAR PrevValue =
    CALCULATE (
        LASTNONBLANKVALUE ( 'Fact'[Date], 'Fact'[Value] ),
        'Date'[Date] < CurrentDate
    )
RETURN
    CurrentValue - PrevValue