I had always thought statements like "Mr. Bennet has two thousand a year" were talking about his gross income, and all the expenses associated with running an estate full of tenant farmers would have to come out of that. But if that's the case, land would have to have a significantly higher return rate than "the Funds" in order to be worth it - otherwise, one would be better off leaving the money in the the Funds, where it would accumulate interest without incurring any additional expenses. So are references to "Mr. So-and-so's ten thousand a year" actually talking about his net profits, rather than his total income?