Who says radio’s dead?  Although broadcast ad revenues are creeping downward, audiences are aging and streaming has surpassed the medium as a vehicle for music discovery, station groups and owners continue to adapt, evolve – and succeed. In its inaugural Deep Dive report, Billboard assesses the radio industry today and provides a glimpse of its future by comparing streaming and radio users, automobile audio usage, the growth rates of programming formats -- and by looking at why labels and artists still need airtime even in a streaming world.  Broadcasters discuss how they are tapping into double-digit growth in digital radio advertising;  finding success with hyper-local programming; and in a video interview with three of radio’s most influential programmers, what goes in to making a hit