Assuming F4 has your 10/1/08 BD, then this should work:

=INT((F7-$F$4)/(365/12))

F7 has the date in question. The result will return the number of whole
months since the anniversary. And the definition of a whole month is 365/12
or 30.4 days.

"Steve" wrote:

I have read through the past posts and havent found exactly what I am looking
for. I need to have a formula that will tell me how many months an employee
has worked after his anniversary THIS year, up to his anniversary NEXT year.
I am able to make a formula that will calculate for this year, but when the
year changes, it messes up. EX. Ann. date of 10/1/08. On 11/1/08 it should
say "1", on 12/1/08 is should say "2", on 1/1/09 is should say "3", etc....