I'm glad that Brandt Dainow of Think Metrics has published a study of click through data over at iMedia Connection. Most SEO agencies will not, cannot, do this. Think Metrics is analytics rather than SEO.
The data is fun to look at. I don't agree with the conclusion;
"1st Position Isn't Worth It".
It's no secret that 1st position is rarely the best for ROI. That's not news. What about volume? The first position is often best for volume.
Dainow's figures also lead him to conclude;
"There is no relationship between the position of an advertisement in the Google Ad listings and the chance of that ad being clicked on."
I guess this is a study of AdWords which appear on the first page. There's certainly a big difference in clicks between page 1 and page 3. No secret here either. In fact, just to repeat, there can often be a difference in the number of clicks you get at position 1 than you do at, say, 8.
Of course, you don't have to believe me. You can drop your bids to position 8 and see what happens.