The show pushed Fox to become the number one U.S. TV network amongst adults 18–49, the key demographic coveted by advertisers, for an unprecedented eight consecutive years by 2012. Its success also helped lift the ratings of other shows that were scheduled around it such as House and Bones, and Idol, for years, had become Fox's strongest platform primetime television program for promoting eventual hit shows of the 2010s (of the same network) such as Glee and New Girl. The show, its creator Simon Fuller claimed, "saved Fox".
For how many years was Fox the highest rated network with young adults because of American Idol? 
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The show pushed Fox to become the number one U.S. TV network amongst adults 18–49, the key demographic coveted by advertisers, for an unprecedented eight consecutive years by 2012.
The show pushed Fox to become the number one U.S. TV network amongst adults eighteen-forty-nine, the key demographic coveted by advertisers, for an unprecedented eight consecutive years by twenty twelve.
For how many years was Fox the highest rated network with young adults because of American Idol? 