I'd like to see that as a function of land and population. I'm willing to wager that, because there's only so much land and crops, there's only so much demand

I'd like to see that as a function of land and population. I'm willing to wager that, because there's only so much land and crops, there's only so much demand for labor--unless you want like one person per bushel or something silly. Meanwhile, the rest of the population continued to grow.