Inflation-Induced Overearnings
构建理论模型分析通胀对名义和实际收益的影响，发现固定成本导致经营杠杆产生超额收益，但最终成本上升或需求下降会逆转这一效应。
This article presents a simple theoretical model to explore the effects of inflation spikes and ongoing inflation on nominal as well as real earnings. When the same inflation rate applies uniformly to all pricing and cost terms (including the fixed costs) and when unit sales are assumed to be stable, a firm’s earnings theoretically will grow at the inflation rate. If fixed costs truly are fixed (even to some degree), however, operating leverage will come into play and create a spike in inflation-driven overearnings. An ongoing inflation could sustain overearnings in both nominal and real terms and may even accelerate growth in such overearnings. This overearnings will continue until rising costs compress profitability or rising prices supress sales demand. At that point, the result may be an earnings decline that could be even further exacerbated by downside effects of operating leverage.