The model developed uses a measure of the discrepancy between price and marginal cost to estimate the effects of domestic demand fluctuations on the degree of oligopoly coordination in the US steel industry. Due to the importance of imports, however, domestic demand fluctuations occur whenever market demand and/or import supply shift. Consistent with several recent game-theoretic models, our results show that coordination among US steel producers tends to be weakest when market demand is high and import supply is low
