How much time did an user logged in?

Hi Anonymous ,

Based on my test, you could refer to below steps:

Add index for your data in query editor:

Apply it and create below formula:

Column = var a=[Index]-1
return CALCULATE(MAX(Table1[Date]),FILTER('Table1','Table1'[Index]=a))

Result:

Now you could use the [Date] column to minus the [Column].

Regards,

Daniel He