The History and Development of Canada’s Personal Income Tax: Zero to 50 in 100 years finds that the tax, which began as a small wartime revenue generator, has morphed into a costly, complex behemoth that’s difficult to administer and makes Canada uncompetitive. In fact, when compared to U.S. states, Canadian provinces have seven of the eight highest top combined rates, with Nova Scotia, Ontario, Quebec, New Brunswick, P.E.I. and Manitoba all over 50 per cent.