IAB

Internet advertising soaked up record revenues of $42.8 billion in 2013, the Interactive Advertising Bureau announced in a new report on Thursday.

A 17 percent increase over 2012's results, last year's number helped the online ad industry beat the $40.1 billion in sales seen by traditional TV advertising. That achievement marked a first for online ad sales. Mobile ads contributed to the growth in 2013 with $7.1 billion in revenues, a 110 percent jump from the $3.4 billion generated the previous year.

"The news that interactive has outperformed broadcast television should come as no surprise," IAB president and CEO Randall Rothenberg said in a statement. "It speaks to the power that digital screens have in reaching and engaging audiences. In that same vein, the staggering growth of mobile is clearly a direct response to how smaller digital screens play an integral role in consumers' lives throughout the day, as well as their critical importance to cross-screen experiences."

Who's spending all this money on online ads?

Retail businesses continued to make up the largest chunk of Internet ad spending, accounting for 21 percent of the total, according to the IAB. Financial services took second place at 13 percent, followed closely by the auto industry at 12 percent.

And how are companies spending the money from their online ad budgets?

Display-related ads took in $12.8 billion, or 30 percent of the year's total revenues, the IAB said. Digital video ads accounted for $2.8 billion, a 19 percent rise from 2012. And search revenues reached $18.4 billion in 2013, up 9 percent from the previous year.

Created independently by the New Media Group of PwC, IAB's Internet Advertising Revenue Report is based on survey data about online ad revenues from Web sites, online services, free email providers, and other businesses that sell Internet advertisements.