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-- Yahoo Search Marketing Pay Per Click Advertising
---- Fluctuations in avg.cpc & position
awardmasters - 9:01 pm on Aug 6, 2008 (gmt 0)Thread source:: http://www.webmasterworld.com/yahoo_search_marketing_overture_ppc/3714721.htm
It is most likely because some (or many) advertisers for those keywords are moving in and out. Some may be hitting budgets, others may only want to run ads during certain hours, etc.
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