Measure to calculate date difference between action date and the date before

Question

I have a table in power bi as below:

User id.	First date	Last date
X.	5 july 24	15 july 24
X.	15 jun 24	20 june 24
X.	3 apr 24	17 apr 24

I need a measure to calculate date difference between first date and previous last date

...i tried many measurea

Answer 1

you can try to create a column

Column =
VAR _last =
    MAXX (
        FILTER ( 'Table', 'Table'[Last date] < EARLIER ( 'Table'[Last date] ) ),
        'Table'[Last date]
    )
RETURN
    DATEDIFF ( _last, 'Table'[First date], DAY )

or create a measure

MEASURE =
VAR _last =
    MAXX (
        FILTER ( ALL ( 'Table' ), 'Table'[Last date] < MAX ( 'Table'[Last date] ) ),
        'Table'[Last date]
    )
RETURN
    DATEDIFF ( _last, MAX ( 'Table'[First date] ), DAY )