Gibrat's Law and the Growth of Canadian Cities

This paper tests for the existence of diseconomies of size for Canadian cities using Gibrat's Law. If diseconomies of size are not present, then the growth rate of cities is shown to contain a unit root. Therefore, testing for Gibrat's Law is equivalent to testing for unit roots commonly found in the time series literature. Our tests indicate that Gibrat's Law cannot be rejected for the seven largest Canadian cities.