Another calculating age when page loads question

Thanks for helping me with the other's. Can you help me with this one?
How to calculate 67 years and older as of 1/1/2011 - 12/31/2011,  then subtract the birthdate from that. That will give me the number of days. Divide that number by 365 and take the integer of the result and I  will get the number of years as of the end of12/31/2011. Just see if that number is >= 66 or >= 67.

I hope that makes sense.
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