Historical perspective is provided in Chart II. This trend of fewer owners generally earning a larger percentage of market revenue is further emphasized by looking at the revenue share of the top four owners in the Metro market. The data suggest that this trend has substantially tapered off over time. The large increase in concentration that occurred from March 1996 to November 1997 can be largely attributed to the relaxation of the local radio ownership rules required by the 1996 Telecom Act, as can the smaller, but still obvious increase that occurred from November 1997 to November 1998. The subsequent change from November 1998 to March 2000 is less noticeable.
(3 Due to the use of “Metro market revenue” to compute shares (see footnote 12), it is possible for some concentration ratios to slightly exceed 100%. In such a case, for purposes of graphing, any concentration ratio that exceeds 100% is changed to 100%.