Convert date into month format not working

[arlu1201]

This is just baffling me.....

I am using Excel 2003 for this. - I have a set of dates in column A in the format - dd-mmm-yy (eg. 03-Nov-11). I want to extract the month from these dates, so i used the formula =month(A1) and i got 11. So far so good.
Then i wanted the 11 to show as "Nov". So i custom formatted the cell B1 (containing 11) to mmm. This gave me "Jan". Which is utterly weird. Why should it give me Jan?

On the contrary, if i use the "Choose" function, it works properly. Why doesnt it work in the first case?

[martindwilson]

why not just use = a1 formatted as mmm?

[arlu1201]

Martin....this is cool....i never thought of that...sometimes we just overlook the small details and go after the big ones..

[daddylonglegs]

Why should it give me Jan?

Excel counts dates from 1st jan 1900 so 11 - treated as a date is 11th Jan 1900, hence "Jan" when you format as "mmm". To get Nov you need to format the date as mmm, so you can do that in B1 by using just

=A1

and formatting as mmm

or you can use this formula in B1

=TEXT(A1,"mmm")

The display is the same but the second is text rather than a formatted date.....

[arlu1201]

Thanks daddylonglegs......this was really making me mad...when it should have worked if you look at it literally...