CVA Wrong Way Risk Multiplier Decomposition and Efficient CVA Curve

Credit value adjustment (CVA) is an adjustment added to the fair value of an over-the-counter trade due to the counterparty risk. When the exposure to the counterparty changes in the same direction as the counterparty default risk the so-called wrong-way-risk (WWR) must be taken into account. Calculating CVA with WWR has been a computationally challenging task especially because it has to be done frequently. In this paper, we start with the fact that the ratio of CVA with WWR to CVA under the independent exposure and default assumption depends on the means and standard deviations of exposure and default probability and their linear correlation. The CVA WWR ratio is then decomposed into two factors, a robust correlation and a profile multiplier with further economic insight into the CVA WWR ratio. The distribution free approach in this paper entails an efficient algorithm of curve based CVA WWR calculation. A numerical study illustrates the algorithm and its benefits