Mere talk of tariffs will spur some consumers to run out and buy big-ticket items, or stockpile smaller ones, on the theory that prices will soon rise. That behavior, alone, could make prices increase. If Trump announces tariffs on his first day in office, as he has suggested, some prices could spike immediately.

The president-elect said that he would impose the across-the-board tariffs on Day 1 and that they would stay in place until Canada, Mexico and China halted the flow of drugs and migrants.

President-elect Donald Trump on Monday promised massive hikes in tariffs on goods coming from Mexico, Canada and China starting on the first day of his administration, a policy that could sharply increase costs for American businesses and consumers.