Leverage Dynamics without Commitment
研究了企业在无法事先承诺政策、可连续调整杠杆时，杠杆率的均衡动态。发现杠杆棘轮效应导致股东逐步增发债务，但资产增长和债务期限使杠杆缓慢均值回归，投资者预期未来发债并提高信用利差，完全抵消新债的税收优惠。
ABSTRACT We characterize equilibrium leverage dynamics in a trade‐off model in which the firm can continuously adjust leverage and cannot commit to a policy ex ante. While the leverage ratchet effect leads shareholders to issue debt gradually over time, asset growth and debt maturity cause leverage to mean‐revert slowly toward a target. Investors anticipate future debt issuance and raise credit spreads, fully offsetting the tax benefits of new debt. Shareholders are therefore indifferent toward the debt maturity structure, even though their choice significantly affects credit spreads, leverage levels, the speed of adjustment, future investment, and growth.