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The primary city airport is George Bush Intercontinental Airport (IAH), the tenth-busiest in the United States for total passengers, and twenty eighth-busiest worldwide. Bush Intercontinental currently ranks fourth in the United States for non-stop domestic and international service with 182 destinations. In 2006, the United States Department of Transportation named IAH the fastest-growing of the top ten airports in the United States. The Houston Air Route Traffic Control Center stands on the George Bush Intercontinental Airport grounds.

When did the U.S. Department of Transportation name IAH as fastest growing of U.S. airports?
2006