It's the highest amount ever spent on online ads during a year's first semester since the report was first issued in 1996, although the growth failed to match the 23 percent registered during 2011's first half. At the height of the economic crisis, this market shrunk 5 percent in the first half of 2009.
In what will be good news for Google in particular, search remained the biggest ad category, accounting for 48 percent of all spending, up 2 percentage points from last year's first half. Search ad spending grew 19 percent.
Display ads, in the form of banners, digital video commercials, multimedia and sponsorships, captured 33 percent of the spending, down 3 percentage points. Display ad spending grew only 4 percent, but the digital video commercials sub-segment increased its revenue 18 percent.
Spending on ads delivered via mobile devices jumped significantly to $1.24 billion, almost doubling the revenue registered in 2011's first half.
In a issued Thursday, IAB and PwC officials said the results indicate that the U.S. online ad market is healthy and strong, with attractive growth opportunities in mobile and video.