The "Derived Depreciation Areas" component makes it possible to determine new asset values based on asset values that have already been determined. The derived depreciation area uses mathematical formulas to determine values based on values in ‘real’ areas, such as the difference between depreciation in two depreciation areas. The system then manages these new values in the derived depreciation area.

Derived depreciation areas function the same as real areas in regard to reporting and value field display. You can also post the values of the derived areas to Financial Accounting.

You define the formula for the derived depreciation area in FI-AA Customizing (Define depreciation areas). In the formula for a derived area, you can use up to four real areas. The arithmetic operations allowed are addition and subtraction. It is possible to mix the calculation rules. This includes using proportional values from real areas in the calculation.

When defining the formula, it is up to you to make sure it is reasonable. Make sure that the key of the derived area is larger than the keys of the real areas it is based on. A derived area "03" can be derived from the real areas "01" and "02" but not from areas "04" and "05."

You can also specify that the derived depreciation area is only for reporting. The system then does not subject the area to value checks (such as the check for positive/negative net book value).