We demonstrate that the severity of financial constraints has declined over time for two reasons: (i) improved access to external funds as evidenced by a decreased reliance on internal cash flows, and (ii) an inward shifting investment frontier with reduced investment opportunities. The decline in financial constraints coincides with the documented diminishing sensitivity of investment to cash flows, yet we show that cash flows remain a determining factor in helping constrained firms overcome restricted access to external capital. There is a flight-to-quality during economic shocks, where the adverse effects following periods of tightened credit are particularly pronounced for smaller firms, with larger firms appearing largely unaffected.

中文翻译：

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金融约束的演变

我们证明，财务约束的严重程度随着时间的推移而下降，原因有两个：(i) 获得外部资金的机会有所改善，这表现为对内部现金流的依赖减少，以及 (ii) 投资前沿向内转移，投资机会减少。财务约束的减少与有记录的投资对现金流的敏感性下降相吻合，但我们表明，现金流仍然是帮助受约束的公司克服获得外部资本受限的决定性因素。在经济冲击期间会出现向质量转移的现象，信贷紧缩期后的不利影响对小公司尤为明显，而大公司似乎基本不受影响。