90% of dollar bills full of cocaine traces

Yesterday I read in a dutch newspaper that 9 out of 10 dollar bills in the U.S. have traces of cocaine on them. People from the University of Massachusetts  did checks in 30 cities all over the world. In Washington DC it’s even 95%. Two years ago it was only on 66% of the bills. Analysts think that maybe because of the crisis people use more coke. I dunno coke is pretty expensive, so I would expect more people in the U.S. to use meth instead. In Canada and Brazil also a lot of bills have coke traces between 80 and 85 %. In China only 12% and Japan 20%. They did not test Europe but it will be about the same as in Canada, I guess. The myth from people in the U.S. that people in Europe use a lot more drugs then they do is officially nonsense with this research I think. Well after living in San Francisco I already knew this was the case myself.