It would be worth to have a look at the below link (by Chip Pearson) which
explains how excel stores date and time..

http://www.cpearson.com/excel/datetime.htm

If this post helps click Yes
---------------
Jacob Skaria


"The Message" wrote:

Is there a way to make date formats read 1/1/2009 when you converty them to
mmm-yy, instead of them staying at their original format.

Basically, if a cell reads 3/3/2009 and I format it to read Mar-09, the
actual cell value still reads 3/3/2009. I want this to revert to 1/3/2009 to
ensure another worksheet can pick this up.

THe other worksheet in effect, only recognises dates formatted to the first
of each month before converting them to mmm-yy. If anything is different to
the first of each month, it does not recognise it.

Any help would be greatly appreciated.