Subtract Same Row Dates

Hi, NPC 

You can try the following methods.

Column:

Previous Date =
MAXX (
    FILTER (
        'Table',
        [Completed On] < EARLIER ( 'Table'[Completed On] )
            && [Equip_Num] = EARLIER ( 'Table'[Equip_Num] )
    ),
    [Completed On]
)

Previous Status =
CALCULATE (
    MAX ( 'Table'[Status] ),
    FILTER (
        'Table',
        [Equip_Num] = EARLIER ( 'Table'[Equip_Num] )
            && [Completed On] = EARLIER ( 'Table'[Previous Date] )
    )
)

Follow = IF([Status]="REA"&&[Previous Status]="SFT",1,BLANK())

Date_Difference = IF([Follow]=1,[Completed On]-[Previous Date],BLANK())

Is this the output you expect?

Best Regards,

Community Support Team _Charlotte

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