【英语国际】美国信用评级下调基本知识问答

The move by Standard & Poor's to cut the U.S. credit rating added more uncertainty to global markets already buffeted by concerns over debt crises and slowing economic growth. Here are answers to some of the most important questions.

Q: What's the difference between triple-A and double-A-plus? That doesn't sound so bad.

A: It isn't so bad -- and there isn't much difference. Technically, double-A-plus is considered 'high-grade' credit, while triple-A is 'prime.' The likelihood of getting paid back by a double-A-plus credit is considered 'very strong,' while a triple-A credit's likelihood of paying you is 'extremely strong.'

The U.S. is a special case, given its status as the world's largest economy and printer of the world's reserve currency. Because so many investors want to hold Treasurys and the dollar, the U.S. can get away with a slight credit-rating downgrade without having to pay more to borrow.

Q: Luxembourg is rated triple-A. Is the U.S. really a bigger risk?

A: No. Luxembourg is a perfectly sound credit risk, but it lacks many of the advantages of the U.S. For example, because it is part of the euro zone, it doesn't have a large printing press to back its debt.

Q: So the principal and interest payments on Treasurys are safe. But will the downgrade cause their value to drop?

A: In the short term, probably not. Don't forget that, right now, investors are most concerned about a weakening U.S. economy, an environment that should support Treasury prices until recession fears ease.

Meanwhile, the so-called bond vigilantes, who are supposed to enforce fiscal discipline on profligate governments by dumping their bonds and jacking up their borrowing costs, have been notably absent since the financial crisis began.

For better or worse, Treasurys are the largest fixed-income asset class in the world, by far, and the likelihood of default is next to zero. The dollar is, for now at least, the world's reserve currency, meaning non-U.S. central banks will have to keep buying Treasurys.

Q: But won't some investors be forced to sell?

A: Maybe a few: some pension funds, university endowments and other big investors are required to hold triple-A securities. But managers are considering tweaking their rules to allow them to keep Treasurys.

U.S. banking regulators have confirmed that the downgrade will not force banks, which have big Treasury holdings, to raise any more capital as a cushion against losses.

Q: What is the likely effect on interest rates?

The market has been bracing for this downgrade for a while, so it is possible that most of the increase in yields has already taken place.

Investors will likely respond more to inflation or deflation pressures, central banks and economic growth than to what one ratings firm says.

标准普尔(Standard & Poor’s)下调美国信用评级的举动加剧了全球市场的不确定性，此前全球市场已经因债务危机和经济增长减缓的担忧而受到冲击。以下是一些最重要问题的答案。

问：AAA评级与AA+评级的差异何在？AA+评级听起来也没那么糟糕啊。

答：它确实不是太糟糕，二者之间也并没有很大的差异。严格来说，AA+评级被认为是“优质”信用，而AAA则是“最优质”。AA+信用偿还债务的可能性被认为“非常高”，而AAA评级偿还的可能性“极其高”。

美国是个特殊案例，这缘于它作为世界最大经济体以及全球储备货币发行国的地位。由于有那么多的投资者想要持有美国国债和美元，美国可以躲过信用评级略微下调产生的不利后果，不必因此而增加借贷成本。

问：卢森堡的评级为AAA。美国的风险真的比卢森堡大吗？

答：不是这样。卢森堡的信贷风险很小，但它缺乏美国所具备的许多优势。比如说，它是欧元区成员国，没有强大的印钞机来支撑其债务。

问：这么说美国国债本息偿付都是安全的。但评级下调是否会导致美国国债的价值下降？

答：短期内可能不会。别忘了，目前投资者最担心美国经济的不断走弱，这种环境下美国国债的价格应能受到支撑，直到有关衰退的担忧缓和下来。

同时，自本次金融危机开始以来，所谓的“债券警卫”一直明显缺位。“债券警卫”原本应当抛售大肆挥霍国的债券，推高它们的借贷成本，从而起到加强财政纪律的作用。

不管怎样，美国国债毕竟是世界上最大的固定收益资产类别，其违约可能性接近于零。美元至少眼下还是世界储备货币，这就意味着其他国家的央行不得不继续购买美国国债。

问：但一些投资者会不会被迫抛售？

答：少数可能会：一些退休基金、大学捐赠基金和其他大投资者依据其投资章程只能持有AAA级债券。但这些机构的管理人员正在考虑调整投资章程，以使得其能够继续持有美国国债。

美国银行业监管机构已经确认，不会因评级下调而要求银行提高损失拨备。银行业持有大量美国国债。

问：评级下调可能对利率产生什么影响？

答：一段时间以来，市场一直在为此次下调做准备，因此评级下调对债券收益率产生的推升作用可能已大部分被市场所消化。

投资者更有可能对通胀或通缩压力、央行的举措以及经济增长状况做出反应，而不是对一家评级公司说的话做出反应。