Designated Market Area (DMA)®
In addition to reporting radio audience estimates for the Metro and TSA, Arbitron reports radio audience estimates for the Top 50 Television DMAs (ranked on TV households) for the Spring and Fall surveys only, as follows:
Radio audience estimates for DMAs are published in the Radio Market Reports of all Standard radio markets whose Metros are located within the DMA and whose names are contained in the DMA name. For example, radio audience estimates for the San Francisco-Oakland-San Jose DMA are reported in both the San Francisco and the San Jose Radio Market Reports; however, radio audience estimates for the New York DMA are reported in the New York Report, but not in the Nassau-Suffolk Report.
The Designated Market Area is A. C. Nielsen's geographic market design, which defines each television market. DMAs are composed of counties (and possibly also split counties) and are updated annually by the A. C. Nielsen Company based on historical television viewing patterns. Every county or split county in the United States (7) is assigned exclusively to one DMA.