Study says that the average pro will have expenses of $143,000 per year. Thus, a pro has to be ranked between 100-200 to break even financially on prize money alone.
That makes sense. Guys ranked in the 300s and above are playing in Futures tournaments that might pay out 10K to the outright winner of the tournament. Pro Tennis is a tough damn sport, man. It's dog eat dog. The very very top guys are loaded beyond belief, sure. But everybody else is just grinding away, trying to slowly climb the ladder.