[mightyham]

It is complicated because tariffs are not just "passed off". In the real world, tariffs are almost always marginal, meaning each company is willing to absorb some of the cost, ie lower profits. In parent's example, the US has a large steel industry and rail companies relying on imports cannot arbitrarily raise prices because they need to stay competitive with companies using domestic. Markets are also dynamic and simply comparing pre/post price may work temporarily, but for a persistent tariff that metric will become increasingly meaningless as price inevitably fluctuates due to other factors.