Systematic and Unsystematic Risk
A portfolio of securities will be susceptible to both systematic and unsystematic risk. Systematic risk is the risk that the entire market will drop, dragging with it the performance of an individual stock or portfolio. Systematic risk is also referred to as market risk. If the performance of a portfolio drops due to systematic risk, it has dropped because the whole market has dropped, not because of the performance of the specific companies within the portfolio.
Unsystematic risk is the risk that the value of the specific securities within the portfolio will decline due to factors specific to the companies issuing the security (e.g., a decline in the company’s Standard & Poor’s rating). The amount of unsystematic risk in a portfolio depends on the number of securities in the portfolio and the correlations among the securities
