Having had a lot of fun, and having gained a lot of software knowledge and wisdom over the years, I do not look forward to the day when, like an old pro athlete, I have to retire from being a programmer because I physically can't do it anymore.
So, I was pleased to stumble across an IEEE Spectrum Tech Talk article that suggested I don't have much to worry about along that line for quite a while. Here is an excerpt:
Prejudice against older programmers is wrong, but new research suggests it's also inaccurate. A dandy natural experiment to test the technical chops of the old against the young has been conducted—or discovered—by two computer scientists at North Carolina State University, in Raleigh. Professor Emerson Murphy-Hill and Ph.D. student Patrick Morrison went to Stack Overflow, a Web site where programmers answer questions and get rated by the audience. It turned out that ratings rose with contributors' age, at least into the 40s (beyond that the data were sparse). The range of topics handled also rose with range (though, strangely, after dipping in the period from 15 to 30). Finally, the old were at least as well versed as the young in the newer technologies.This is in line with what I already knew about chess. I played a lot of chess when I was a kid. I was told then that a person's chess rating didn't drop all that much during the player's lifetime.
Of course, such a natural experiment can't account for all possible confounding factors.
The article also addresses chess, but a bit ambiguously. Here is a figure the article presents:
It was hard for me to interpret the vertical axis. I am not sure if SD Units represent standard deviation or not. I remember that for I.Q., one standard deviation is about 15 points, but I don't know if there is an appropriate analogy that can be drawn here.
So I looked up Aging in Sports and Chess which presents some experimental results documented in a paper by Ray C. Fair done in 2007. It says that if you are 100% of your maximum ratings by age 35, then you are 99% at age 40, 97% at age 50, 95% at age 60, 93% at age 70, 90% at age 80, and 80% at age 90. So it doesn't look like more than a slow steady decline until people get into their 80s.
As with the Stack Overflow data, it is hard to judge the relationship of data about chess skill to programming skill. But all this data suggests I don't have too much to worry about for a long time.