The relationship between return on assets and their riskiness is one of the liveliest topics in financial literature. In his 1952 landmark article, Markowitz developed a mathematical model that captured this key financial concept. defined risk as the variance of the rate of return of a portfolio. Later, Sharpe hypothesized a positive linear relationship between expected rate of return on an asset and the risk premium associated with that asset. Subsequently, Sharpe tested this hypothesis empirically and found support for his theory. Although portfolio theory specifies the two parameters of this model as ex ante return and risk, Sharpe used ex post data for testing the risk-return relationship. designated the ex post mean rate of return obtained on an an asset as a proxy for expected return and the standard deviation of ex post annual rates of return as a surrogate for risk.