Former Federal Reserve Chairman Paul Volcker

Former Federal Reserve Chairman Paul Volcker

Peter Foley/Bloomberg

Paul Volcker, former chairman of the U.S. Federal Reserve, speaks in New York on Jan. 31, 2012. Analyst at Sanford C. Bernstein & Co. Financial firms have said that the so-called Volcker rule, which bars banks from proprietary trading, may also limit trading profits, once a prime source of Wall Street revenue and bankers’ pay.