In 1970, the market in financial derivatives in the United States and elsewhere was very small by today's standards (there are no reliable figures for its total size), and to trade many of today's derivatives, such as the Merc's S&P 500 futures, would have been illegal. By 1987, derivatives played a central role in the U.S. financial system, which is why the fate of the Mercantile Exchange was so critical to that system. Derivatives markets were also beginning to emerge around the world.

Donald MacKenzie, An Engine, Not a Camera, loc. 31