Clark - 7:27 pm on Aug 31, 2003 (gmt 0)

Did you change anything? Did one of your pages on a particular topic get lots of hits all of a sudden? Do you have a huge amount of traffic (therefore immune to one person skewing results)? Because if you get 100 or 1000 ads in one day, and you get one person visiting your site who is interested in your topic and he starts clicking on advertisers to check out who's advertising in your market, you can easily get that kind of one day skew. The higher your traffic the less this will fluctuate.