IF Statement Amendment

Hi ArchStanton , try this formula.
Logic Used:
When the Created On equals the Resolution Date , return 1 day;
otherwise for resolved cases return an inclusive day count (DATEDIFF + 1).
For active cases the existing behaviour is preserved (you can switch to inclusive there too if you prefer).

Case Length =
VAR StartDate =
    IF(
        ISBLANK( 'Cases'[legacycasecreationdate] ),
        'Cases'[Created On],
        'Cases'[legacycasecreationdate]
    )
VAR IsActive = 'Cases'[statecode] = "Active"
VAR ResDate = 'Cases'[Resolution Date]
RETURN
IF(
    IsActive,
    -- Active: difference between StartDate and now (unchanged behaviour)
    DATEDIFF( StartDate, NOW(), DAY ),
    -- Resolved: handle blanks, same-day, otherwise inclusive DATEDIFF (+1)
    IF(
        ISBLANK( ResDate ),
        BLANK(),
        IF(
            DATEVALUE( StartDate ) = DATEVALUE( ResDate ),
            1,                                          -- same calendar day => 1
            DATEDIFF( StartDate, ResDate, DAY ) + 1    -- inclusive count
        )
    )
)

Notes / rationale

• DATEVALUE(...) is used when comparing StartDate and ResDate so time components don’t make two same-day timestamps look different.

• DATEDIFF(...)+1 gives an inclusive day count (e.g., start = 1-Jan, end = 2-Jan → 2 days).

• If you want inclusive logic for active cases too, change the active branch to DATEDIFF( StartDate, NOW(), DAY ) + 1.

• If you prefer to always return 0 rather than BLANK() for missing Resolution Date, replace BLANK() with 0.

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