The Value at Risk tool is simple to use and involves only one screen designed for you to enter in information about the size of your investment and ten observations for the time period you are considering. It then displays your risk factor variability and your Value at Risk results for a 99% confidence interval, a 95% confidence interval, and a 90% confidence interval.
Value at Risk is a popular method for capturing the downside risk in financial decision making. The Value at Risk tool is designed to answer the question "What is my worst case scenario?" For example, for a confidence interval of 99%, the Value at Risk tool will tell you the worst loss expected one time out of 100.