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Date.IsInPreviousMonth is a Power Query M function that indicates whether the given date(time) value occurs during the previous month, as determined by the system. The function returns a boolean value (true or false).

Compatible with: Power BI Service Power BI Desktop Excel Microsoft 365


Date.IsInPreviousMonth( dateTime as any ) as nullable logical


Date.IsInPreviousMonth checks if dateTime (of type date, datetime, or datetimezone) is in the month prior to the current system date and time, not including the current month.


Determine if the month before the current system time is in the previous month.

// Output: true
Date.IsInPreviousMonth( Date.AddMonths( DateTime.FixedLocalNow(), -1 ) )

Other functions related to Date.IsInPreviousMonth are:

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