Search study shows a 10x difference in traffic between the first listing and the tenth.

At AD:TECH Chicago earlier this week, aQuantive, Inc.'s Atlas DMT released research demonstrating the impact of paid search listings rank on traffic and how marketers can better model and forecast paid search campaigns.

The study found that overall, advertisers should expect about a 10 times difference in potential traffic between the top and 10th rankings. The research further revealed significant differences across the two leading search providers.

On Google, for example, the amount of potential traffic drops more than 40 percent between the No. 1 one ranking and No.2. This statistic supports marketers willing to pay for the top position.

At Yahoo!'s Overture, the drop in potential traffic is more gradual across rankings one through four.

Atlas DMT used data from Atlas Search to analyze the performance of hundreds of millions of impressions and clicks for tens of thousands of keywords.

"Just like any other marketing channel, success for search is about balancing cost and volume. Understanding those trade-offs is the focus of this research," says Young-Bean Song, director of analytics and the Atlas Institute, Atlas DMT.

The insights from the research are expected to be used to inform strategic decisions for search marketing campaigns and tactical executions for specific keywords. In addition to paid search, the principles of the study also apply to paid inclusion and natural search.

Atlas' advice for marketers based on the data:

• Model your search campaigns based on cost, clicks, conversions and rank. The data presented here provides a key component in modeling campaign performance. To model traffic overall, you can look at last month’s average rank, clicks, and conversions to obtain a basis for projecting the overall potential of your campaign.
  
  
• This research has focused specifically on traffic. To build a complete picture, you need to also understand conversion rates. The Atlas Institute is also examining the relationship between rank and conversion rate. Those results will be published in a separate analysis, but make sure that at a minimum you are tracking your conversion rate by search engine.
  
  
• Look at your own data. While this aggregated data revealed a fair amount of consistency in how impressions and CTR drop by rank, each industry is different. Overture and Google distribution also change over time. To obtain the most accurate numbers for your specific situation, you should perform a similar analysis on your own data.
  
  
• Manage CTR in all engines. A 10 percent improvement in the CTR of a listing is a 10 percent increase in clicks. In Google AdWords, improving CTR has the added advantage of decreasing your cost per click (CPC), since Google factors CPC into its AdWords rankings.

"Paying for the number one ranking may not be the best strategy for all advertisers," says Song. "For some marketers the cost of traffic associated with the top ranking may be too high. On the other hand, some marketers are foregoing the top spot, without really knowing how many customers they are losing to their competitors. Most advertisers don't know whether they are paying too much, or needlessly missing out on sales.