>>>I'm using:
>>>
>>>set decimals to 18
>>>?5000.3 + 0.6
>>>
>>>The result is: 5000.900000000001000000 instead of simply 5000.900000000000000000
>>>
>>>Someone could explain me why?
>>
>>Fractional numbers with the exception of currency, which uses a fixed precision BCD format,
>
>Wasn't the currency stored as a 8-byte integer, with decimal pointed shifted four places?

No, it's actually an 8 byte BCD format as I recall, with something like 15 or 16 places of precision. Same idea as BCD, though; Fixed size and decimal precision. If we really had it stored that way, we'd have convenient access to ULARGE structures.