Applications using Decimal versus double . .

Question

I wanted to see if folks were using decimal for financial applications instead of double. I have seen lots of folks using double all over the place with unintended conseque

Answer 1

This is not as obvious as you may think. I recently had the controller of a large corporation tell me that he wanted his financial reports to match what Excel would generate, which is maintaining calculated results internally at maximum precision and only rounding at the last minute for display purposes. This means that you can't always match the Excel answers by manual calculations using only displayed values. His explanation was that there were multiple algorithms for generating the results, each one doing rounding at a different place using decimal values, therefore potentially generating conflicting answers, but the Excel method always generated the same answer.

I personally think he's wrong, but with so many financial people using Excel without understanding how to use it properly for financial calculations, I'll bet there's a lot of people agreeing with this controller.

I don't want to start a religious war, but I'd love to hear other opinions on this.