NEW YORK (AP) -- A new report says revenue from Internet advertising in the U.S. hit a record $31 billion last year.
That's up 22 percent from $26 billion in 2010, the previous record.
The report was released Wednesday by the Interactive Advertising Bureau, an industry group. The study was conducted with PricewaterhouseCoopers.
About half of the ad revenue, $14.8 billion, came from the search category. Those are the text-based ads sold by Google and others, which are targeted to search terms and other keywords.
The fastest-growing category was mobile, with revenue of $1.6 billion in 2011, more than double the $600 million a year earlier. It's still a small part of overall Internet advertising, however.