Abstract: We study aggregate dynamics in models of price-setting with menu costs. We establish three results. First, these aggregate dynamics are well approximated by those of a Calvo model, with a slope coefficient of inflation on real marginal cost that is a simple function of the ratio of kurtosis to frequency of price changes. Second, they are exactly given by a particular mixture of time dependent models that can be readily obtained from the law of motion of price gaps. Third, we can recover these dynamics from the distribution of price changes alone. Implementing this in micro data, we find that Calvo provides a very close fit, though with some modest inflation persistence added.