It is difficult to discern exposures from institutions’ reported credit market posi- tions. Indeed, common data sources such as annual reports and regulatory filings record accounting measures on a large and diverse number of credit market instruments. Ac- counting measures are not necessarily comparable across positions. For example, the economic value of two loans with the same book value but different maturities will react quite differently to changes in interest rates. At the same time, many instruments are close substitutes and thus entail essentially the same market risk. For example, a 10 year government bond and a 9 year high-grade mortgage bond will tend to respond similarly to.
