How to calculate difference between dates in same column?

I want to calculate difference in days between dates located in the same column. This difference would be calculate between one date and the previous date.

Dates are not ordered. I tried the following:

DateDiff("day",Max([Date]) OVER (Previous([Date])),[Date])


DateDiff("day",first([Date]) OVER BinByDateTime([Date],"Year.Quarter.Month.DayOfMonth",3),[Date])

Unfortunately, both of these methods do not work and the second one gives me an error message ("Year function not found").

Could you please help?

(2) Answers