One of the major problems faced by banks is how to manage the risk exposure in large portfolios. According to Basel II regulation banks has to measure the risk using Value-at-Risk with confidence level 99%. However, this regulation does not specify the way to calculate Value-at-Risk. The easiest and most common way to calculate Value-at-Risk is to assume that portfolio returns are normally distributed. The previous crisis shows that the regular methods are unfortunately not always enough to prevent bankruptcy. This study is devoted to compare the classical methods of estimating risk with...