Modern Portfolio Theory and Investment Management

Modern Portfolio Theory (MPT) had its origins in the U.S.A. during the 1950’s, and grew out of attempts by researchers (most notably Markowitz 1952, 1959 and Tobin 1958) to find mathematically ‘efficient portfolios’, that is, security combinations which resulted in maximum expected returns for given levels of risk (normally measured by the variance of investment returns). Unfortunately, the excessive computational requirements as well as the sophisticated mathematics underlying MPT, prevented this academic work from reaching the investment community for most of the 1950’s and 1960’s. Fortunately, the increasing availability (and decreasing costs) of both financial information and computational capacity of computers has now resulted in the widespread use of MPT by academics and practitioners alike, especially in the U.S.A.