Another factor was the efforts of the Federal Reserve to wring inflation out of the economy, marked by Paul Volcker's speech of October 6, 1979, with a series of rises in short-term interest rates. This led to a scenario in which increases in the short-term cost of funding were higher than the return on portfolios of mortgage loans, a large proportion of which may have been fixed-rate mortgages (a problem that is known as an asset-liability mismatch). Interest rates continued to rise, placing even more pressure on S&Ls as the 1980s dawned and led to increased focus on high interest-rate transactions. Zvi Bodie, professor of finance and economics at Boston University School of Management, writing in the St. Louis Federal Reserve Review, "asset-liability mismatch was a principal cause of the Savings and Loan Crisis