The coefficient k is called the capital multiplier and is calibrated in order to be consistent with the 99.9% threshold. An estimate of the loss volatilities leads to the Credir Value-at-Risk straightforwardly. This assumption is exact in the case of normal distributions, but remains incorrect for skewed distributions. However the great advantage of this method applied to credit risk is to get a parametric formula of the Credit value-at-Risk. The parametric formulation leads also straightforwardly to estimate of the marginal contribution and incremental capital of any line of the portfolio. On their side, the loss volatilities can easily be estimated analytically ; as an example, we can modelise the default of an obligors with a binomial law with default probability p. If the loss given default is 100%, the expected loss is
going to be equal to p, and the loss volatility is p 1( − p) .