• by Laurie Sullivan , Staff Writer @lauriesullivan, April 12, 2013

Marketers spent 24% more on paid-search ads across all engines in Q1 2013 -- a slight sequential decline from 25% growth in Q4 2012. But you will find the real numbers in the cost per clicks and return on investments, according to a recently released report. The average CPC rose 7% in the quarter and paid clicks rose 15%. Are you keeping score?

If you are, the Rimm-Kaufman Group Digital Marketing Report estimates that marketers spent 20% more for paid-search ads in Q1 2013 on Google compared with the prior year's quarter, with CPCs rising 8%. Marketers spent 48% more on Bing compared with the same quarter in the prior year, as the engine continued to deliver strong impression growth on expanded keyword to query matching, among RKG clients.

Others have seen similar gains. J.P. Morgan Analyst Doug Anmuth held a call with Rimm-Kaufman Group and Performics earlier this month, where an exec from the latter said U.S. marketers spent 12.4% in the first quarter of this year, with paid clicks rising 10.1% and cost per clicks (CPC) 2.1%, year-on-year. Sequentially, numbers looked flat with 12.3% growth in fourth-quarter 2012, where paid clicks rose 9.5%, and CPCs 2.6%.

Mobile generated 28% of clicks on Google, but just 16% of clicks on Bing. CPCs on tablets eclipsed desktop with marketers spending 162% more compared to the prior-year quarter, according to the RKG report. Smartphone CPCs 190% rose with spend.

Product Listing Ads (PLAs) generated 33% of Google non-brand spend among RKG's client sample. The company makes an interesting observation, however: Competition rose from late adopters coming on board after the Google Shopping transition to a paid model in mid-2012, but return on investment (ROI) for PLAs remains 22% higher than for non-brand text ads.

The report suggests the spending on comparison shopping sites rose 25% in the quarter compared with the prior year, among the RKG clients. Click volume among the paid engines rose 31%.

Shopping.com, prior to eBay rebranding as the Commerce Network, took share by generating 26% of CSE clicks in the first quarter, followed by Shopzilla-Bizrate at 22%. Shopzilla's share has recently declined as their CPCs have risen following the introduction of their Smart Pricing model.