The trade cycle is best regarded, I think, as being occasioned by a cyclical change in the marginal efficiency of capital, though complicated and often aggravated by associated changes in the other significant short-period variables of the economic system.

我认为，贸易周期最好被视为由资本边际效率的周期性变化引起，尽管经济体系的其他重要短期变量的相关变化很复杂，而且往往会加剧这种变化。