第４回金融研究会を開催しました。

(Abstract)

A firm’s operating leverage (OL)—the degree to which its cost structure is fixed rather than variable—is central to operational flexibility and systematic risk. Empirical research has long faced a measurement gap: aggregate proxies mask item-level heterogeneity, while regression-based estimates are noisy and require multi-year windows. Exploiting disaggregated cost data from Japanese manufacturing firms, this study implements an Account Classification Method (ACM) yielding a high-precision, firm-year OL measure. Both COGS and SG&A contain heterogeneous components—material costs and fees co-move proportionally with revenue, whereas depreciation, rent, and labor exhibit fixity and downward inflexibility. Crucially, aggregate COGS appears variable largely as an accounting artifact: inventory adjustments absorb fixed-cost shocks, and inventory itself exhibits sticky-cost behavior. Account-level revenue sensitivities remain stable over 50 years, validating the ACM. Strikingly, regression-based OL estimates show near-zero correlations with all account-based measures, providing evidence of fundamental measurement noise. Cross-sectional analyses reveal positive associations with profitability and negative associations with financial leverage; within-industry sorts confirm higher OL is associated with slightly higher returns. Yet the association is more pronounced for SG&A-based proxies, suggesting the “operating leverage effect” partly reflects intangible investment rather than cost rigidity per se.