자본구조 조정속도에 관한 연구: 기업규모에 따른 이질적 조정속도를 중심으로

Even if a firm sets up a target leverage ratio to maximize its value, it may be deviated from the target ratio for various reasons when adjustment costs are substantial. On the other hand, the firm tries to revert to its target ratio when deviation costs are large enough. Adjustment costs includes not only explicit transaction costs affected by firm characteristics but also investment frictions, institutional arrangements, macroeconomic conditions, and etc. Since it is difficult to measure both adjustment and deviation costs, recent studies on leverage measure adjustment speeds using partial adjustment models which are adequate to reflect the dynamics of capital structure. The purpose of this study is to test the practical application of dynamic trade-off theory and non trade-off theory such as pecking-order and market timing based on the measurement of adjustment speeds of 387 Korean listed firms in the period of 2000-2014. Specially, we focus on the difference in adjustment speeds between large and small firms because firm size difference provides opportunity to discover the relative significance between adjustment costs and deviation costs. The adjustment speed of small firms is slower than that of large firms when small firms pay more transaction costs in financing. On the contrary, the adjustment speed of small firms is faster when they suffer more by being deviated from the target leverage ratio. Important empirical findings of this study can be summarized as follows. First, the adjustment speed is 0.51 when the book leverage ratio is used and 0.54 when the market leverage ratio is used. Such fast adjustments support the trade-off theory postulating that firms try to maintain the target leverage ratio. Second, the adjustment speed of small firms is faster than that of large firms, which indicates that deviation costs are more important than transaction costs. Third, this paper provides various evidence on the effects of firm characteristics on adjustment speeds classified by firm size. Fourth, various robustness tests increase the credibility of our results. Finally, we show that both the determinants of target leverage and the speeds of adjustment toward the target depend upon the choice of the book leverage ratio and the market leverage ratio.