Interest in real-time bidding continues to grow worldwide, but inventory in North America, the largest market for RTB, is seeing slower growth. Media buying and optimization company Accordant Media found that global RTB impressions during the fourth quarter of 2012 were up 61% compared to Q4 2011 and impressions for all of 2012 were up 101% compared to 2011.
In North America, which is the largest and most mature RTB market, RTB inventory was up 41% in Q4 2012, and up 76% year over year.
“If you look at the most recent quarter, there is somewhat of a slowing down in the growth rate, which is why we say it’s still strong, but it’s at a cooler rate,” Accordant co-founder and CEO Art Muldoon told AdExchanger. “But it also might just be because of the power of larger numbers we’re comparing it to.”
Several factors played a role in RTB’s Q4 performance, including the holiday season and the impact of the new Facebook Exchange.
Muldoon said Accordant saw that for the CPMs it paid, the average cost jumped 20% the Wednesday before Thanksgiving and fluctuated, but stayed up, throughout the holidays.
“That shows that this programmatic real-time media buying is being utilized by marketers during an important holiday season,” he added. “This is a strong signal for publishers that there is a good opportunity to monetize inventory.”
However, average CPMs for the quarter were down slightly compared to Q3 2012and year-over-year. The introduction of Facebook Exchange, where CPMs are generally lower, may have affected that, Muldoon noted.
“Think about the overall growth rate in the auction activity,” he said. “If we see, in North America, a 41% increase over the last year just during the quarter, and only a 5% to 10% decrease in CPMs, even with Facebook coming on board during that period, it shows that, in terms of the supply and demand equation, the supply is still being aggressively pursued.”
Accordant works with seven channels—display, video, mobile, social through the Facebook Exchange, email, in-stream audio, and digital out of home.
“The bulk of our buying is display, but our focus for real growth is mobile and video, in the context that we’re increasingly doing cross-screen targeted optimization,” Muldoon said.
Another drop was in click-through rates in North America, with CTRs up only 1% compared to Q4 2011 and down 12% compared to Q3 2012. But that metric, Muldoon said, isn’t as important for advertisers as might be expected.
“We have a variety of performance-related clients who are looking for sales conversions,” he said, “so we are looking for analytics around quality of audience experience and the type of audience that tends to convert instead.”