Currency by the Yard

I was musing about this as I was reading about how naked Société Générale must be feeling after having stripped off 7.5 yards of capital in (so it seems, but the night is young...) trader fraud.

I used to think that, when Wall Street Foreign Exchange traders sold Yen "by the yard" (meaning 10⁹ yen, a U.S. "billion"), I presumed that the New Yorkers were making a humorous and self-deprecating comparison between their business and the rag trade, next door on the Lower-East Side.

In fact, it is Londoners who invented it. They were abbreviating the word "milliard", the old French/British word for a 10⁹, when the word "billion" used to mean 10¹² (for which we say "trillion") following the numerical system known as échelle longue. The word "billion" is still considered confusing semantically (did you mean 10⁹ or 10¹², old chap?), and phonologically is too close to million or trillion in a noisy trading environment, where people seem to be rather sensitive to silly mistakes.

I didn't know that.