After Google and Yahoo announced their Q3 results, you saw a lot of analysts quote data from comScore and Nielsen about how many searches Google gets a month.
Comscore reports around 5B total searches/month in the US across all search engines in July 2005.
If you believe those numbers, you might calculate as John Battelle did:
Average revenue per search (yes, any kind of search, not just paid): 12 cents. It was around a dime in late 04.
However, I think comScore and Nielsen are wrong in these estimates. Not wrong by a little, but wrong by a lot. And it throws into question a lot of the analysis that people do about Google and the search engines.
How much traffic does Google really get? I believe the number is close to 1.2 Billion searches per day, worldwide. I believe Yahoo gets over 200M a day worldwide. In other words, Google and Yahoo are getting around 40 Billion searches worldwide every month. I formulate those estimates based on conversations with several search engine experts.
And yes, I do think Google gets about 6-7X the number of searches that Yahoo gets, despite the market share numbers that are often published.
For Google and Yahoo, it's likely that the US represents at least 45%+ of their search traffic. Combined they are at least 18B/month in the US.
How come comScore and Nielsen both think that Google and Yahoo are about getting 3B/month in the US? I think they are making a big scaling error when they take their panel data and extrapolate. Or they are missing a lot of searches in their counts somehow.
The only other citation I can find that contradicts comScore and Nielsen's authority is this story from Danny Sullivan, way back in February 2003. If you take Dannny's Google 250M/day number from Feb 2003 and multiply by 30, you get 7.5B. If the US was 50% of that back in 2003, that's still much greater than comScore is reporting Google's search traffic is TODAY - 2.5 years later.
So either Google's numbers have gone down since 2003, or comScore and Nielsen are way off. Of course, both Yahoo and Google subscribe to these services. I wonder what they think of the accuracy of these reports?
UPSHOT: I believe comScore and Nielsen are vastly underestimating the total search traffic that Google (and Yahoo) gets.