I think the far left is percentile. As in, the 99th percentile is very lean.
Okay, I originally thought that, but does that mean for ages 20-29 column, at the bottom, that 28.9 - 38.9 is the body fat percentage, which would be classified as very poor? That doesn't seem right...
Maybe. In that age column, those are the highest body fat numbers.
I agree, it is an odd table though. I guess I see it like a BMI chart; for a female 20-29 y.o., the difference between a "poor" rating and a "very poor" rating would be a body fat %age of 27.1-28.9.