Value At Risk: Uses And Abuses

Value at risk (or “VAR”) is a method of measuring the financial risk of an asset, portfolio, or exposure over some specified period of time. By facilitating the consistent measurement of risk across different assets and activities, VAR allows companies to monitor, report, and control their risks in a manner that efficiently relates risk control to desired and actual economic exposures. Nevertheless, reliance on VAR can result in serious problems when improperly used, and would‐be users of VAR are advised to consider the following three pieces of advice: ▪ First, VAR is a tool for firms engaged in total value risk management. Companies concerned not with the value of a stock of assets and liabilities over a specific time horizon, but rather with the volatility of a flow of funds, are often better off eschewing VAR altogether in favor of a measure of cash flow volatility. ▪ Second, VAR should be applied very carefully to companies that practice “selective” risk management those firms that choose to take certain risks as a part of their primary business. When VAR is reported in such situations without estimates of corresponding expected profits, the information conveyed by the VAR estimate can be extremely misleading. ▪ Third, as a number of recent derivatives disasters are used to illustrate, no form of risk measurement including VAR–is a substitute for good management. Risk management as a process encompasses much more than just risk measurement. Indeed, risk measurement (whether using VAR or some of the alternatives proposed in this article) is pointless without a well‐developed organizational infrastructure and IT system capable of supporting the complex and dynamic process of risk taking and risk control.