All except for 6 weeks or so, all I have to keep track off is the decades. On Jan 1, 1940, I was 0+, in 1950 I was 10+, in 1960 I was 20+, etc. 2005, I'm 65+.
Hey, I can do it in my head! :)
Alex The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. -- Bertrand Russell