Rating downgrades are known to make subsequent downgrades more likely. We analyze the impact of this 'downward momentum' on credit portfolio risk. Using S&P ratings from 1996 to 2005, we estimate a transition matrix that is insensitive to and a second matrix that is sensitive to previous...

Theory of financial intermediation gives contradicting answers to the question whether banks should diversify or focus their loan portfolios. Our aim is to find out which of the two strategies is predominant in the German banking market. To this end we measure diversification for all German...