Calculate difference between rows by group

Hi Unknown ,

Thank you for the sample data, I created the same data as yours to test it, and finally succeeded in calculating the result you want to achieve. As the following shows, it is my testing result:

The measure I use is as follows, you can try it:

_date =

if(SELECTEDVALUE('Table'[number])="", BLANK(), DATEDIFF(

CALCULATE(MAX('Table'[date]),FILTER(ALL('Table'),'Table'[company]=MAX('Table'[company])&&'Table'[Index]<MAX('Table'[Index])&&'Table'[number]<>"")),SELECTEDVALUE('Table'[date]),DAY)

)

Best regards,

Community Support Team Selina zhu

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