Umbrella is way more memorable and iconic than Firework even. People compare their recurrent sales are funny since Umbrella was released 4 years before Firework . And keep in mind that Umbrella even has less views on youtube than Avril Lavigne's GF
How dumb do you have to be to compare digital sales from 2007 with digital sales from 2011? Or youtube views? Anyone who's older than 18 knows the answer to this one.