Does anyone know of good SEO vs PPC ctr history studies

[DoRM]

I have read some like http://www.seomoz.org/blog/mission-imposserpble-establishing-clickthrough-rates  This is over a year old now

and http://www.marketingprofs.com/chirp/2012/8504/paid-vs-organic-search-are-ppc-ads-winning-the-google-click-wars-infographic

Please let me know of some other good studies that have been done that show how the CTR continue to go down on commercial terms for most searches cause google is putting in more stuff.

[SanketPatel]

Hi Dorm

Here i found a great post written by Danny Goodwin on : Organic vs. Paid Search Results: Organic Wins 94% of Time

Hope you found this post interesting..

[DoRM]

I have read that one in the past and it seems different that a lot of other ones I have read.  Do you have any other examples like the one the have on seo moz? thanks,