Concentration:
Hoskins, McFadeyn and Finn in their explanation of market concentration use a chart of concentration ratios for U.S. Communications industries from 1994 which indicate that the four firm concentration rate, measuring percent of market share in TV and Radio stations (CR4) is 60 and the 8 firm concentration rate as 87. Since then we have gone through an even more intent period of concentration led by Clear Channel and its acquisition of multiple radio stations in multiple markets. But there are new kids on the block.
