I wondered what the financial relationship with local stations is, so I spent a little time Googling it.
My local station is WAMU. It's apparently now the top NPR station in the country and is the top news station, even among commercial stations, in the DC area.
It pays 16% of its income to American University, its hosting organization. This is apparently an unusual arrangement. Most hosting universities pay the radio station, not the other way around. It also pays an undisclosed amount to the national NPR organization. I wonder why the chart in the first post doesn't show payments from affiliate stations to the NPR organization? It's a significant income stream for NPR. About 40% of WAMU's income comes from corporate donations, and it rewards those corporations with 15 second informational segments (but understand, these are not commercials.) Most of the rest comes from individual donors, like my wife.
Updated information
is hard to come by, but I found a
2013 annual report. WAMU had a decent reserve of money, but then spent it all when it built a new building. It's possible that by building the new building, they will no longer have to pay 16% to American University.
WAMU used to play bluegrass in the afternoons, but decided to shift to all news. News is expensive. They had to hire a bunch of people. But it payed off. Turns out, Washingtonians don't much like bluegrass and do like news. They are now very popular but are barely keeping ahead of their expenses, especially with building a new broadcasting center.