I don't know about French banks, but belgians don't say "octante", seems to be a common misconception! They say "quatre vingt", like the French. Swiss don't either, it's either "quatre vingt" or "huitante"
There are a couple of papers comparing language in children’s numerical ability and performance (particularly speed and accuracy). [1]
The theory espoused was simpler and quicker languages like Chinese (well at least the Chinese number system with quick mono-syllabic base ten based counting) resulted in faster computing ability with fewer errors than English with specialized words like eleven and eighteen rather than “tenty-eight”. The more exemptions to simple logic the slower and more error prone computing was for humans. French on this metric was at the bottom of the pile with polysyllabic non-simple words like quatre-vingt-dix.
I like the idea of Walloon or Fribourg French counting being a sort of high frequency trading hack for people of the 19th century with shorthand like “ûtante.”
Thanks, very interesting! It took watching my children having to learn French numbers to realize just how difficult (and unnecessary) it was. Then you get used to it and it becomes second nature. I wonder if the added difficulty persists into adulthood...
I still think that "octante" was used on the trading floor, but it was more than 10 years ago, and I was not trading myself...