This paper provides new evidence of how macroeconomic conditions affect capital structure choice. We model firms’ target capital structures as a function of macroeconomic conditions and firm-specific variables. We split our sample based on a measure of financial constraints. Target leverage is counter-cyclical for the relatively unconstrained sample, but pro-cyclical for the relatively constrained sample. Macroeconomic conditions are significant for issue choice for unconstrained firms but less so for constrained firms. Our results support the hypothesis that unconstrained firms time their issue choice to coincide with periods of favorable macroeconomic conditions, while constrained firms do not.

Credit migration is an essential component of credit portfolio modeling. In this paper, we outline a framework for gauging the effects of credit migration on portfolio risk measurements. For a typical loan portfolio, we find credit migration can explain as much as 51% of volatility and 35% of economic capital. We compare through-the-cycle migration effects, implied by agency rating transitions, with point-in-time migration, implied by EDF™ (Expected Default Frequency) transitions, and find that migration of point-in-time credit quality accounts for a greater fraction of total portfolio risk when compared with through-the-cycle dynamics. In a stylized analytic setting, we show that, when controlling for PD term structure effects, higher likelihood of moving away from the current credit state does not necessarily imply greater risk. Finally, we review methods for generating high-frequency transition matrices, needed for analyzing instruments with cash flows or contingencies whose frequencies are asynchronous to an available transition matrix. We further demonstrate that the naïve application of such methods can result in material deviations to portfolio analytics.

We develop a Q theory of investment under financing constraints. The firm invests and saves optimally facing convex costs of external equity, overhang from outstanding debt, and collateral constraints on new borrowing. Overhang and costs of external equity discourage investment. Conversely, firms anticipating collateral constraints experience a side benefit from investing as installed capital relaxes future constraints. Empirical tests support the model. Conditional on average Q, investment is lower for equity issuers and for firms with large debt overhang. The Kaplan and Zingales and the Whited and Wu indices are used as proxies for future collateral constraints. Consistent with the model, both indices enter investment regressions positively.