安全幅度 meaning in English

margin of safety

Because the value of securities , including those of the exchange fund paper on the liability side , fluctuate in response to changes in interest rates , we have a practice of keeping in the currency board account us dollar assets that exceed the monetary base by a safe margin
由于证券价值包括负债方的外汇基金票据及债券会受到利率变动的影响而有起跌，因此我们向来都是确保货币发行局帐目内的美元资产超出货币基础一个安全幅度。
Take the situation in which us dollar interest rates rise more than hong kong dollar interest rates . the value of the us treasury securities may fall , in absolute terms , more than that of the exchange fund paper , so that the backing may become insufficient if there is no safety margin
就以美元利率的升幅超逾港元利率的情况为例：美国国库券实际价值的跌幅可能会超过外汇基金票据及债券，这样若没有预先定出安全幅度，货币基础便可能得不到十足支持。