Rounding Standards - Financial Calculations

Question

I am curious about the existence of any \"rounding\" standards\" when it comes to the calculation of financial data. My initial thoughts are to perform rounding only when the da

Answer 1

The first and most important rule: use a decimal data type, never ever binary floating-point types.

When exactly rounding should be performed can be mandated by regulations, such as the conversion between the Euro and national currencies it replaced.

If there are no such rules, I'd do all calculations with high precision, and round only for presentation, i.e. not use rounded values for further calculations. This should yield the best overall precision.