According to three SMU Assistant Professors of Finance Tang Yuehua, Hu Jianfeng and Gennaro Bernile, traders may have made up to $256 million in illicit profit by getting early word of the Federal Reserve's decision to loosen or tighten the money supply. They cited “robust evidence” of abnormally large price movements and imbalances in buy and sell orders from September 1997 through June 2013, when Ben Bernanke was chairman of the Fed. The researchers said that the moves occurred before and during the time that reporters at the Treasury Department were given advance notice of the Federal Open Market Committee statements in periods known as lockups.