Time for new SEM vs SEO data!

With all the SEM & SEO data available on the web, it's exceedingly surprising to me that AFAIK there is *no* data more recent than 2004-06 on what % of search clicks go to paid vs organic results.

There's recent data on the CTR of different organic positions, data on the CTR of different AdWords positions, but no public data I can find showing what % of overall search clicks/traffic go to AdWords vs organic listings.

I've looked high and low on the wider web, so please show me to be a weaker searcher than you, and let's find some accurate, recent data on the topic.

Why is this important? Well for starters, I think that people will be surprised with the extent to which growth in AdWords has come at the expense of organic traffic. Otherwise put, I'm not so sure Google's monetizable inventory is growing much anymore, and suspect that most of the growth in paid search is net-zero growth = coming from organic as opposed to net-new monetizable queries.

Should that be the case, then:
a) valid questions can be posed as to the expected future efficacy of SEO efforts;
b) companies can expect (and plan/budget for) continued increases in AdWords vs SEO traffic, and the higher overall CPA that entails;
c) Yahoo, Bing, Apple and other search aspirants can knowledgeably think about what strategic moves they'll have to make with their own SERPs in order to compete with Google for users *and* distribution partners

In June 2004 I wrote up the below for a client who was asking me essentially the same question, and while I can't recall where I got the data from then, I'm reasonably sure it was as close to accurate industry data as was available at the time:

The major SE’s vary wildly in percent of click-throughs monetized through paid search:

Google = 27%
Yahoo = 35%
AOL = 50%
MSN = 70%
Ask Jeeves ~ 75%

Those numbers are an indicator of who's doing the best job of monetizing inventory, but also of who has the most future upside should they better monetize search. To that end, here's another piece of data that quantifies that growth potential relative to the varying current monetization levels for each engine. Namely, the % of paid versus free links at several major search engines:

Yahoo - 29%
Ask Jeeves - 52%
AOL - 44%
Google - 50%
MSN - 45%


Dividing the % of click-throughs to paid search by the % of listings that are paid, you get a measure of the engines' effectiveness at maximizing click-throughs per paid listing:

Google - 27%/50% = 54%
Yahoo - 30%/29% = 103%
AOL - 50%/44% = 114%
Ask Jeeves - 75%/52% = 144%
MSN - 70%/45% = 156%

This shows how much room there is for Google to grow its revenues independent of search query volume. Likewise, Yahoo can throttle up monetization by 40-50% before it reaches the upper limit already attained by Ask Jeeves & MSN. As for those two, future growth for them will have to come from growth in search query volume and/or CPC growth, both of which are largely out of their control.

So, anyone out there have such data? We know Google does, but I'll bet they consider that about as proprietary as CocaCola does their secret recipe. [AWA - I'd love your thoughts, but expect your access to such data is greatly exceeded by your marching orders not to divulge #:^)]