If we have an annual return that we're looking at, we can find a completely riskless asset with an annual return-- it would be a government bond that matures in one year.

如果我们可以查看各项资产的年度收益，我们可以找到一个零风险,且达到预期年度收益的资产项目-,也许是一年期的政府债券。

耶鲁公开课 - 金融市场课程节选