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It has fractions of 1/2, /4, /8, /32, /64. But not /16.

There must be an interesting reason why, anybody know?



Even to this day US treasury bonds are priced like that. It's starting to get silly now with 'quarters of a 32nd of a dollar' and such (ie. 1/128, but written as 1/4 1/32 due to the limits of human comprehension).


Specifically, the limits of trader comprehension, which are somewhat more restrictive.


Okay there, Super Fractions Fella.


There’s a 1/16 on there.

I assume it is a historical oddity. NYSE prices were done in fractions up until a few years ago.


Bond futures still are [1]:

* Minimum Price Fluctuation: One thirty-second (1/32) of one point ($31.25), except for intermonth spreads, where the minimum price fluctuation shall be one-quarter of one thirty-second of one point ($7.8125 per contract).*

As are some bond-like derivatives, eg MAC swap futures, which are quoted in quarters of thirty-seconds [2]. The way prices are written out is maddening - consider yesterday's settle [3]:

107'247

This means 107 and 24.75 thirty-seconds!

[1] https://www.cmegroup.com/trading/interest-rates/us-treasury/...

[2] https://www.cmegroup.com/trading/interest-rates/swap-futures...

[3] https://www.cmegroup.com/trading/interest-rates/swap-futures...


It has its origins in the use of Spanish dollars and various related bits of gold that could be reliably cut in half, in early American history.

I think a lot of companies got away with using binary floating point maths without introducing errors, for assets priced in those power-of-two fractions.




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