When someone asks I always tell then much older. My favorite when someone asks is I tell them I am going to be seventy in a few months. Then I get the ... you don't look your age....comment. I am actually 20 years younger.
My philoshopy is ....who really cares? .... whats the point... ? It is a number that has no real bearing on anything. It does not bother me to tell ...but since the answer is so ...trival ... I just have fun with the asker.