That depends on the type of the financial calculations you're doing. Certainly accounting and billing shouldn't be done in binary floating point formats. Financial modelling and forecasting calculations aren't exact calculations, and the intermediate library functions for binary floating point may suffer less rounding error than practical alternatives. Also, computational efficiency comes into play once you're at the scale of spending millions of dollars per year on hardware and electricity for financial modelling.

Also, since IEEE-754-2008, there are decimal IEEE-754 floating point numbers, which are useful for some types of financial calculations.