europeforvisitors - 1:55 pm on Oct 13, 2003 (gmt 0)

Also, I was not aware that it was a long weekend in North America (though that would affect mainly the impressions and consequently the click-throughs ...but not the EPC).

A long weekend could result in lower payments per click if advertisers suspended their ads for the weekend, or if advertisers with a day-trader mentality went to the beach instead of bidding.

In any case, I think it's hard to discern trends on the basis of limited experience and anecdotal evidence. There are just too many variables. Take my category, European travel: As we get into the low travel season, demand (and therefore bids) are almost certain to drop for some destinations, products, and services; but in some cases, demand and bids may go up. Who can say, for example, that hotel demand in Venice during Carnival or in Switzerland during the ski season won't offset the off-season drop in demand for Eurailpasses and camper rentals? Experience with affiliate sales may provide some guidance, but only some, because AdSense can provide targeted ads for so many topics that affiliate programs don't address--e.g., Greek yacht rentals, mail-order alphorns (the ideal Christmas gift for the adventurous tuba player), or naturist resorts in Croatia. Even if advertisers' bids stayed the same, seasonal changes in user demand (a.k.a. the "look-to-book ratio") would affect revenues and effective CPM.