根据Bloomberg的说法，现在美国公债的加权平均到期期限是5年左右。

According to Bloomberg, the weighted average maturity of all American public debt is now around five years.

youdao

There have also been one hundred-year bonds and there have also been perpetuities that-- in the UK, for example, the British Consoles-- have no expiration date and they have infinite maturity.

还有更长期的一百年债券,还有一种永续年金,比如说英国的大英统一公债,没有过期日,永不到期

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