Forum Moderators: open
If you have 30 or more results per page, it will be hard not to found what you are looking for in those 30 first results, so very few people would go to the second page. However, expecting that the average user does not change the default of ten in their preferences, i would expect less than a 20% of users actually going to the 2 SERP, maybe less.
85/10/5
With other SEs it could be different...
75/15/10
There are many other factors that may come into play, particularly the search query.
A related thread with some interesting statistics...
Mapping Local Google Usage [webmasterworld.com]
For example, if they are searching for a local news story involving a person by the name of "Fred Sappington" they are likely to sift through the results until they find a link that looks like what they are looking for - even if that means going 4 or 5 result pages in.
If they are searching for something like "Red Sox Tickets" they are likely to feel the top ten results, and more likely the top 5, will be what they need.
Those who know how to format their search queries to return the most relevant results are probably not going past page one.
Analysis of your statistics will show you how savvy your searching audience is.
Say if you are looking for buying something, then perhaps the queries seem to be shorter, but does this mean there could be more people going to other pages? Becoz of the theory that longer the search query the more likely you will be in the first page, conversly the shorter the query the more likely you will search more pages!
I always review the logs and amend pages accordingly to try and "trap" new search items that I haven't thought of and get into the top 10 for those items.
But my experience is that people are tring to find what we have on site, and therefore do end up looking a little further.
If your competition have great sites, and are in the top 10 for relevant search terms, then I would say you really need to be in the top 10.
In the example I give, our site is pretty much the *only* site that has decent content (ultra-narrow field hobby site).
TJ
Analysis of a Very Large AltaVista Query Log [citeseer.nj.nec.com]
But more interestingly:
What makes a good search engine? [stlcu.com] from Computeruser.com
The article mentions the "rate of abandonment" of Teoma and states that it went from 40 percent in December of 2002 to 19 percent in January 2003.
That is only 19% of the people clicking on one of the Search engine results actually came back to the search engine to check others.
I'm sure Google checks this stuff as well as a certain percentage of SERPS carry click throughs and they have the toolbar data.
That is your answer. It just depends on how much spam Google dishes up on the serps, as to how far the punter feels they have to search.
If you are looking for a hotel in a particular location, or to buy contemporary furniture, you may have to wade through 10 pages of Google to get a reasonable selection. 90% will be affiliate sites that add little to your search for knowledge.
If you are looking for tourist information in a particular country or information on a named castle in Scotland, then the first page will give you all the info.
The more competitive the keyword search, the more likely Google results are to be full of spam, and less likely to be of relevance to the user - mainly because people like us are hell bent on getting our own site onto the first page.
Therein lies Googles great weakness at the moment - spam filters, what spam filters!
So "how many people visit the 2nd page on Google? " is a bit like "how long is a piece of string? "