Mission ImposSERPble: Establishing Reliable Click-Through-Rates (CTR)

by Casey Szulc

What are the click-through-rates (CTR) for each organic position in a search engine ranking page (SERP)?  SEO aficionados have been pondering this question for years, and given the volatile nature of SERPs, it is an incredibly difficult question to answer.  Any given SERP changes on a day-to-day basis as domains compete for top rankings and as Google constantly tweaks its algorithm.  While it may be difficult, establishing a reliable CTR curve is extremely valuable in estimating the amount of traffic your website will receive.

“All men by nature desire knowledge of click-through-rates.” – Aristotle 340 B.C.

Initial Studies

AOL’s leak of massive amounts of private-user data in 2006 allowed the creation of some of the first CTR curves.  Recent studies by Enquiro Search Solutions and Optify have enabled a better understanding of click-through behavior and have produced some interesting results.  Although these studies were conducted at different times (Enquiro in 2007, Optify in December 2010), they have yielded similar CTR curves.

The graph shows the click-through-rates for each organic position in the SERP from both studies.  We can easily see the value of a number one rank in terms of click-through.  Optify and Enquiro found average CTR of 36.4% and 27.1% for the first position.  We notice a significant drop from the first to second positions and another drop for positions below the fold (#5-10).  It is interesting to observe similar trends in both studies despite the fact the organizations conducted them a few years apart from each other.  As SERPs change over time, do we see a constant CTR behavioral pattern emerge?  Will the curve have a similar slope in another 3 years?  The only certainty we have is this: search is constantly evolving.  Social signals are playing increasingly important roles. Google Places, News, and Shopping results have invaded the SERPs, pushing higher ranks below the fold.  How does this affect the future of CTR?  How do branded keyword CTR curves differ from non-branded keywords?  Click-through behavior poses many questions that are difficult to answer, but that will not keep us from trying.

“Attacking that battle station is not my idea of courage.  Establishing reliable CTR, on the other hand, is the most courageous thing a man can do.” – Luke Skywalker

What’s up Next from Slingshot SEO

Slingshot SEO’s own Research & Development team is conducting a click-through study to effectively establish a reliable CTR curve.  One of the most fascinating goals of this study will be to establish long-tail CTR, along with exact.  After all, long-tail traffic is just as important, and comparing the two can help us pick keywords more effectively.  It would be interesting to see how the long-tail CTR curve compares with exact CTR, and how the variances of the two distributions compare.  Our study hopes to explore the behavioral patterns of search and help answer the following questions:

1.    What is the CTR curve for exact organic U.S. results?
2.    What is the CTR curve for long-tail organic U.S. results?
3.    How does the CTR curve for branded keywords compare with unbranded keywords?
4.    How do our results compare with studies previously conducted on CTR?

We are currently analyzing our client data in hopes of determining reliable answers.  Our sample set of click-through data is constantly expanding, and a full report will follow once we obtain a large enough sample set to provide reliable results.  Until then, I leave you by sharing a snippet of our data: click-through-rates for a number one position.  Based on our current sample set, we observe a 25.22% Exact CTR and 7.78% Long-Tail CTR for a position one rank. Stay tuned for a full report later this summer.

“I have never advocated war except as a means of finding true CTR curves.” –Ulysses S. Grant