Looking at paid clicks, or referrals, as a % of total search queries, we see a fairly familiar picture.

However, not all queries are created equal. As Jeremy Crane pointed out many queries do not lead to referral. Many of the unfulfilled queries are probably due to searchers not finding what they’re looking for. Many queries are also informational and can be answered right there on the SERP.

As you can see, Google answers the query on the top of the SERP with a handy conversion calculator, while Yahoo! doesn’t. Instead, Yahoo! offers paid results from Calibex and BizRate.

For users, it’s great to get the desired information right there on the SERP, without having to click-through to another page. For search engines, it’s a missed opportunity to monetize a search.

Thus a more appropriate online metric for measuring search monetization might be paid referrals as a % total referrals.