Sorry, but those are quarter to quarter growth rates - which, for seasonal industries, need to be year-to-year instead (unless he shows what these same quarters

Sorry, but those are quarter to quarter growth rates - which, for seasonal industries, need to be year-to-year instead (unless he shows what these same quarters did in the previous years). He said that it is 18% higher in 2008 Q3 than 2007 Q3. It could be that every year the big jump is from Q3 to Q4! And, perhaps, every year, the quarterly jumps from Q4->Q1, Q1->Q2, Q2->Q3 are relatively small. Also, as someone noted in the TC comments, this is all in USD, which I presume is safe, but I don't know what fraction of ad sales are logged in international currencies, and the dollar has gained recently.