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How many USCF national master are there?

Definitely just being a national master will not be good enough to earn a living n chess. I guess you have to be a grand master to do so. But some NMs do earn some money as tournament prizes or by coaching. I would think almost all if them have a day time job.
I am primarily interested about how many in this thread....
I quit teaching school in December 2012 to teach chess full time. I do quite well financially.

But I bet not all NMs are in a good shape like you are with primary source of income from Chess. I would assume only at GM level you can think of that irrespective of your context or other conditions.

Making a living from teaching ain't the same as making a living from playing. Yes, vast numbers of golf, tennis and other make a living at country clubs etc teaching. But the number who make a living actually playing is an order of magnitude higher than it is in chess. I've made next to nothing from chess. I never even tried, since there were so many other far more lucrative alternatives. Millionaire Chess is changing that landscape in a big way, giving those who reach NM and beyond more options to continue playing than were available when I reached that level a generation ago.
What about the masters that have dipped below 2200? (Sorry if this has already been addressed)
My link will not show that. I am sure there are quite a few of those, but I'll let that be someone else's homework :)