A conjecture on the distribution of firm profit
  A common assumption of political economy is that profit rates across firms or sectors tend to uniformity, and often models are formulated in which this tendency is assumed to have been realised. But in reality this tendency is never realised and the distribution of firm profits is not degenerate but skewed to the right. The mode is less than the mean and super-profits are present. To understand the distribution of firm profits a general probabilistic argument is sketched that yields a candidate functional form. The overall properties of the derived distribution are qualitatively consistent with empirical measures, although there is more work to be done. 
Ian Wright