@NourHaridy Yeah that's nice ! I wonder if some other function like log_10 would better deal with "exponential-like" fluctuations that we quite often see. I will send you some analysis with f(y(x)), f(-y(x)), varying y() and f() !
@NourHaridy Yet, predictable rate interests do matter in financial products. Would you borrow and invest 10 million DOLA, knowing that the interest rate could suddenly go up to 30% ?