After my trip to de USA i wanted to change some USD in Barcelona, they offer me 1.63 USD for each Euro. That's the worst rate I ve ever seen. They told me that they were the only one in the airport and it's not true. There is a Bank aswell, which of course, offered me a much better rate.
BE CAREFUL IF YOU WANT TO EXCHANGE MONEY IN BARCELONA'S AIRPORT. DON'T CHANGE IN GLOBAL EXCHANGE.