In recent years, however, the "index inclusion" anomaly seems to have diminished considerably (Cusick 2001) as the familiar process of identification, exploitation, and eventual attenuation or elimination takes hold. For example, analysis by the investment bank J. P. Morgan suggests that in the late 1990s and in 2000 it was fairly reliably profitable to buy stock if it seemed probable that a company might be added to the United Kingdom's leading stock index, the FTSE (Financial Times -Stock Exchange) 100, while selling those companies at risk of being deleted. Since 2000, however, the strategy's profitability "has been eroded as it has become increasingly arbitraged" (Loeys and Fransolet 2004, p. 16).

Donald MacKenzie, An Engine, Not a Camera, loc. 462