Historians have agreed the impact was small for the United States but have debated its effects on Canada. After the treaty took effect, there was a large increase in Canada's exports to the United States and a rapid growth of the Canadian economy, especially in southern Ontario and Nova Scotia. Canadian exports to the United States grew by 33% after the treaty, but American exports grew by only 7%. Within ten years, trade had doubled between the two countries. For nearly a century, Canadian economists saw the reciprocity era as a halcyon period for the Canadian economy.