We use new hand-collected data from corporate filings to study the drivers of corporate capital structure adjustment. Classifying firms by their adjustment frequencies, we reveal previously unknown patterns in their reasons for financing and the financial instruments used. Some are consistent with existing theory, whereas others are understudied. Many leverage changes are outside of the firm’s control (e.g., executive option exercise) or incur negligible adjustment costs (e.g., credit-line usage). This implies a lower frequency of proactive leverage adjustments than indicated by prior research using accounting data, suggesting that costs of adjustment are higher, or the benefits lower, than previously thought.

We document that (i) debt-to-equity ratios and levered equity betas negatively covary with the market risk premium in distressed firms; (ii) the negative covariance generates negative alphas among those firms. We build a dynamic credit risk model to understand the negative covariance between equity betas and the market risk premium, via endogenous and dynamic debt financing over the business cycles. Because of endogenous debt financing and distress, our model naturally connects the negative failure probability-return relation to the positive distress risk premium-return relation.