The Searchlight Digital Blog has an interesting post that illustrates the percentage of click-throughs you'd get based on a specific Google ranking. The analysis performed by Searchlight covers over 36 million queries and more than 19 million clicks.
The interesting data comes from the explanation from Pete, the blog post's author:
Where this gets really interesting though is when you look at what can happen if you own most of the real estate on a good SERP. The top four results put together account for over two thirds of all clicks that will happen (68.69% in total). The top ten taken as a whole will give nearly nine tenths! (Actual total figure - 89.69%).Drop onto page two, and you’re basically stuffed. Unless the term gets huge traffic, you’re not going to.
In a way, this information is troubling, however. The discussion on Sphinn concerns individuals. NickWilsdon, for example, is quoted as saying: "That shows the effect of Google pushing up these authority sites into top positions. Eventually they will just leave scraps for everyone else."
I guess we're all hoping that day never comes.
Forum discussion continues at Sphinn.