'MONTH' FORMAT DAX NO LONGER WORKING (ALWAYS RETURNS JANUARY)

[ey00016]

Hi guys,

I have a report which includes dynamic text on the first page to display the name of the previous month (e.g. today, March 13th, it displays 'FEBRUARY').

This was working perfectly fine for months up until now, where my formula will only return 'JANUARY'.

Reporting Period = UPPER(FORMAT(MONTH(TODAY())-1,"MMMM"))

The MONTH(TODAY())-1 part is returning '2' AKA February so that is working fine, but as soon as I use 'FORMAT' to turn the number into text, it defaults to January.

Any ideas why this might be happening?

The only thing that has changed since it stopped working is an update to Windows 11 - I wonder if this is the cause and some settings need updating somewhere?

[Greg_Deckler · Accepted solution]

@ey00016 I don't see how that ever worked. I would think it should be:

Reporting Period = UPPER(FORMAT(EOMONTH(TODAY(),-1),"MMMM"))

A 2 would literally be January 1st, 1900 because dates are decimal numbers where the integer portion is the number of days since midnight December 30th, 1899.