Why not just look at the NPR page we're discussing, which says 13% of public radio station revenue is from federal funds? 13% of 31% is 4%.
Edit: The 13% is from all government funds, not just federal.
Edit: The 13% is from all government funds, not just federal.
Random example from an NPR member station's web site:
KCRW is supported, in part, by the Los Angeles County Board of Supervisors through the Los Angeles County Department of Arts & Culture. The Department's Organizational Grant Program helps fund a wide variety of arts, culture, and music programs that you hear on air each day!