Estimation of Distress Costs Associated with Downgrades Using Regimeswitching Models

We use a unique dataset of bond downgrades from a niche rating company that has been found to be reacting faster to publicly available information than its competitors. Using regime-switching models we propose risk measures to quantify stock return disturbances (distress costs) associated with the timing of downgrades. These risk measures are based on the Capital Asset Pricing Model (CAPM) and use the estimated parameters of the regime-switching models. We observe a noticeable switch from a low-volatility to a high-volatility regime one day before the day of downgrades. On average the volatility in stock returns triples around the time of downgrades, and the stock return process remains in the high-volatility regime for about three days. Using our proposed risk measure we find that stock returns are associated with distress costs of about 22*d% (where “d” is the daily market price of risk) over a window of 10 days before and after downgrades. These costs can be further separated between bond-rating companies that are designated by the SEC as nationally recognized to rate debt and those that are not.