The Bank of Canada is widely expected to leave its main interest rate unchanged at 2.25% on Wednesday, extending its hold for a seventh consecutive decision. The outlook comes as policymakers assess the fallout from a sharp deterioration in Ottawa-Washington trade ties following the collapse of trade talks between the United States and Canada last month. All 12 economists surveyed by The Wall Street Journal last week forecast no change, saying central bank officials are unlikely to overreact to the breakdown in negotiations.