counting number of months to a specific age

[Hayes]

Help, I'm at a loss. I'm needing to know as of 12/31/11 how many months until a person reaches age 66 + 3 months. I have their birth date but again I need it to calcuate from 12/31/11.

Thanks to all that can help

 

[baitmaster]

=(year([birthday]-[start date])-1900)*12+month([birthday]-[start date])

 

[Timothy.w.Hayes]

=(year([birthday]-[start date])-1900)*12+month([birthday]-[start date])

I'm not sure that this includes the +3 months.. does it?

 

[Scott Huish]

If you are using a version of Excel prior to XL2007, you will need to load the Analysis Toolpak for this:

=DATEDIF(DATE(2011,12,31),EDATE(A1,795),"m")

Format as General.

 

[Hayes]

Thanks everyone this is what I ended up using with $C8 being the birth date

=66*12+3-DATEDIF($C8,DATE(2011,12,31),"m")