Broadcast-television advertising has suffered from audience fragmentation as channels have proliferated.

频道（数量）激增，观众群过于分散，广播电视的广告业务深受其害。

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Wielding a black Magic Marker, he charted the big bang of channel expansion and audience fragmentation that has propelled television history so far, from the age of the three networks, each with a mass audience, to the hundreds of cable channels, each serving a niche audience twenty-four-hour news, food, sports, weather, music and on to the dawning age of Internet video, bringing channels by the tens of thousands.

NEWYORKER: Streaming Dreams