The actual loss under this head, which we disregard even in reckoning net income and charge to capital account, may be called the windfall loss.

这个项目下的实际损失，我们甚至在计算净收入和记入资本账户时都忽略不计，可以称为意外损失。

But there is a difference between the supplementary cost and a windfall loss in that changes in the former are apt to affect him in just the same way as changes in his gross profit.

但补充成本与意外损失之间存在差异，因为前者的变化对他的影响与毛利润的变化一样。