Explaining the distribution of firm growth rates

Empirical analyses on aggregated datasets have revealed a common exponential behavior in the shape of the probability density of corporate growth rates. We present clear-cut evidence on this topic using disaggregated data. We explain the observed regularities proposing a model in which firms' ability to take up new business opportunities increases with the number of opportunities already exploited. A theoretical result is presented for the limiting case in which the number of firms and opportunities go to infinity. Moreover, using simulations, we show that even in a small industry the agreement with asymptotic results is almost complete.