In 1990, the GDP of Canada was $550 billion as measured in Canadian dollars, and the exchange rate was that $1 Canadian was worth 88 U.S. cents. In 2000, the GDP of Canada was $1070 billion as measured in Canadian dollars, and the exchange rate was that $1 Canadian was worth 72 U.S. cents. By what percentage did the GDP of Canada increase from 1990 to 2000 in U.S. dollars?