Judging from the discussions which occur over and over in on-line forums, the number of Delphi developers who might benefit from such a discourse is larger than first imagined. A final resultant can never be more accurate than the least accurate operand. In preparing a portion of his income tax return, Joe records some amounts rounded to the nearest dollar while others are rounded to the nearest penny. In the above example, the computed tax due should be rounded to the nearest dollar to reflect the fact that some amounts were only recorded to this level of accuracy. As a programmer, only you can decide when a resultant is final and should be rounded.
Common sense is the best available guide.
Financial resultants must obviously be finalized before money can be exchanged. Final means final . An all too common mistake is to round for display only while continuing to carry extra digits internally. In other words, what the user sees is not what he gets. This is generally not a good plan and can cause as many problems as improper rounding.