Car Radio: Off.

     The hosts of a car radio call-in show that's aired on Public Radio for 25 years are retiring and will stop recording new shows in the Fall.
     But old shows may continue till, well, forever!

     Look at the ancient TV shows Public TV continues to air long after the hosts are dead. like Lawrence Welk, whose show ran for 28 seasons on TV, ending in 1981 (that late??). He died in 1992, but the programs continues being rebroadcast to this day.
     If you want to find out if anyone watches, just replace it one night with something less, er, old-fashioned?
     I'm not sure if "Click and Clack", the brother-mechanic hosts on NPR will have the same staying power. How long will people listen as the model cars get older and older...