You might think of yourself as a long-term investor with your cute little retirement fund, but that’s nothing compared to an investment that recently paid out to Yale University. Twelve years ago, the university’s rare books and manuscripts library purchased a bond issued by a Dutch water authority to fund the construction of a pier. The thing is, the bond pays out in perpetuity, and that water authority still exists, so Yale checked to find out whether it was still earning interest. It is.

The college didn’t have an investment in mind when they bought the bond: it was for their rare books and manuscripts collection, and a water bond from 1648 is a pretty neat old manuscript to have.

It’s been earning interest all the time, though, which means that the goatskin parchment that they paid $20,000 for in 2003 has earned a sweet, sweet €136.20, or $153, in interest. They didn’t say whether the pier still exists, though.

The bond is actually older than Yale itself, which wasn’t founded until the 18th century.

Yale to Be Paid Interest on Dutch Water Authority Bond From 1648 [Bloomberg]

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