pdq--go to:
http://www.npr.org/about/aboutnpr/publicradiofinances.html

The first thing you'll see is the pie chart of revenue. You will see that while the direct dole from the Feds is relatively small, NPR gets nearly 16% of its revenues from Federal, State, and Local taxes, and from CPB, which is a Federally created umbrella organization for NPR, PBS, etc.

I believe this information was noted by somebody earlier on in this thread; now you can see it for yourself. If you are adroit at annual financial statements, a bunch of those are available, too.

Good reading.