It occurs to me that sometimes jokes go out of date. For example:

What do you call a taxi pulled by a team of oxen?
Answer: a cattlehack

The problem is that nobody calls a taxi a "hack" anymore. And we only use oxen for hamburger. Jokes about a rotary-dail phone, or a phonograph, or a steam engine, or a Studebaker, or old advertising slogans, or dead movie stars, or out-of-office politicians, just don't work any more. I hear jokes like that in old movies and wonder if younger generations get the point. I guess Time Marches On.
Howard