Credit: Marcus Hamilton and Madeleinne Daepp
Sizes of some 30,000 companies traded publicly on U.S. markets from 1950-2009, measured by their sales (controlling for inflation and GDP growth). The relatively rapid growth of smaller companies near the beginnings of their lifespans account for the ragged lower portion of the chart, as well as the relatively steep initial sales increases. As companies reach maturity, their sales tend to level off.