FWIW, front office is the one place where floating points for money might be sensible, because in most cases in the front office you don't care about pennies. I

FWIW, front office is the one place where floating points for money might be sensible, because in most cases in the front office you don't care about pennies. Instead, what you want to get right is derivatives ("risk"), which you compute with finite differences ("bumps") or somewhat more advanced methods (adjoint automatic differentiation, basically the backward propagation algorithm). So, yeah, if you deal with risk and PVs (in other words, maths) rather than actual cash flows, sure, knock yourself out, use floats. That does not invalidate the general advice to avoid floats for money (which is probably why you were downvoted).