Re: What do we expect?
Don't know why you feel the need to post this rather obvious observation as AC.
I suspect if the BCS (of which I'm a member) analyzed their membership data they would see similar.
Also look at the university data, back in 1980 few university places for Computing, over the decades the number of places has massively increased, so you would expect there to be fewer people 50~60 with Computing degrees (and even fewer 60+).