The procedure was mainly used in the real estate industry for valuations. The consideration that a property has less depreciation in the first few years of its life than in the later has been taken into account in this formula. The Real Estate Valuation Ordinance (ImmoWertV) has been in force in Germany since July 1, 2010. In § 23 ImmoWertV, a linear depreciation is now provided for as a rule.
With this procedure, the age depreciation has a parabolic course.
Age reduction according to Vogels
This method is based on empirical studies of purchase prices. At the end of the total period of use, there is still a residual value of 20%.