But even if one were to take the Trump Administration’s tariff formula seriously, it makes an error that inflates the tariffs assumed to be levied by foreign countries four-fold. As a result, the “reciprocal” tariffs imposed by President Trump are highly inflated as well.
Though in effect the formula for the tariff placed on the United States by another country is equal to the trade deficit divided by imports, the formula published by the Office of the US Trade Representative has two additional terms in the denominator that just so happen to cancel out: (1) the elasticity of import demand with respect to import prices,
ε, and (2) the elasticity of import prices with respect to tariffs,
φ.
https://www.aei.org/wp-content/uploa...425.png?x85095
The idea is that as tariffs rise, the change in the trade deficit will depend on the responsiveness of import demand to tariffs, which depends on how import demand responds to import prices and how import prices respond to tariffs. The Trump Administration assumes an elasticity of import demand with respect to import prices of four, and an elasticity of import prices with respect to tariffs of 0.25, the product of which is one and is the reason they cancel out in the Administration’s formula.
However, the elasticity of import prices with respect to tariffs should be about one (actually 0.945), not 0.25 as the Trump Administration states.
Their mistake is that they base the elasticity on the response of retail prices to tariffs, as opposed to import prices as they should have done.