U.S. President Donald Trump showed off a giant chart on Wednesday full of new “reciprocal” tariffs, which start at 10 per cent and grow steeper for countries with larger trade deficits with the U.S. But experts quickly noticed that these numbers don't add up.

For nations that treat us badly, we will calculate the combined rate of all their tariffs, nonmonetary barriers and other forms of cheating.” — President Donald Trump, in remarks announcing global tariffs,

The Trump administration's tariff calculations appear on paper to be a simplified math of America's trade relationships.