One peculiar property of this--incidentally, at every point of time this thing holds, this is time to maturity.

顺便说一下这个公式一个特别的性质,这个等式在任何时候都成立,这是贷款剩余期限

耶鲁公开课 - 金融市场课程节选

A peculiar property of this is that the mortgage balance falls slowly at first and then it gradually picks up; it's just a property of this formula.

其中一个特别的性质是,刚开始抵押贷款余额降得很慢,渐渐的,越降越快,这就是这个公式的性质

耶鲁公开课 - 金融市场课程节选