Tree fuggers and world economy. Way more to it than those numbers tell.
I love trapping, it's fun, it's challenging, it's educational, it's hands on interactive. Think of this...... A rifle hunter can shoot a coyote at 500 yards. So, he can cover 500 yards in the other direction too, making his kill area 1000 yards. A bow hunter with an effective range of 50 yards can cover 100 yards. A Trapper can cover an area the size of the pan on his trap, 4 square inches, a snare 10" in diameter, it's pretty intimate to trap a critter.
I will openly admit I don't think I was ever a "Good" trapper, but we usually covered expenses for our week long vacation and sometimes made enough to pay hunting club dues. BUT, I would have made more profit if I had worked the week at McDonalds with way less expense.
That's why you don't have the number of trappers today compared to the 70-80's.