Amount conversion rules
Correct rate, verify no inverse rates
Rounding rules for EUR (maybe NCU)
Conversion rates must not be overwritable on input
Notes:
The reference text is Council Regulation 1103/97
ARTICLE 4; The conversion rates shall be adopted as one euro expressed in terms of each of the national currencies. They shall be adopted with six significant figures. The conversion rates themselves must not be rounded or truncated when making conversions. The conversion rates shall be used for conversions either way between the euro and the national currency units. Inverse rates derived from the conversion rates shall not be used. Monetary amounts to be converted from one national currency unit into another shall first be converted into a monetary amount expressed in the euro unit, which amount may be rounded to not less than three decimal places and shall then be converted into the other national currency unit. No alternative method of calculation may be used, unless it produces the same result.
ARTICLE 5; Monetary amounts to be paid or accounted for, when a rounding takes place after a conversion into the euro unit according to article 4, shall be rounded up or down to the nearest cent, Monetary amounts to be paid or accounted for which are converted into a national currency unit shall be rounded up or down to the nearest sub-unit, or in the absence of a sub-unit to the nearest unit or according to national law or practice to a multiple or fraction of the sub-unit or unit of the national currency unit. If the application of the conversion rates gives a result which is exactly half-way, the sum shall be rounded up.
There are checklists on the FEE web site. BASDA (Business Accounting Software Developer’s Association) has prepared specifications for detailed tests. Systems Modelling Ltd. performs certification tests on software using specially designed test cases. As a free “take-away”, two examples follow.