Ertragsteuerparadoxa: Ursachen und Erklärungsansätze

It is a well known phenomenon that investment decisions are often seriously distorted by income taxes: Investment projects, which are not profitable before considering taxes, may turn out to be profitable after taxes and vice versa. The article describes different forms of income tax driven distortions and asks for the reasons of these aneutralities. Some given explanations resort from misunderstandings and errors. Within an income tax system only the adoption of the economic profit concept avoids tax distortions, as in this case the present value of an investment project remains untangled by income taxation. Beyond this concept only cash-flow based tax systems may guarantee tax neutrality, but these cash-flow tax concepts do not belong any more to income taxation but rather to consumption tax systems. Within income taxation a new approach is presented in which amortisation and depreciation follow the disinvesting process (Kapitalfreisetzungspfad) calculated with the internal rate of return of the investment project. This concept may also be applied for the non-distorting tax treatment of financing tools. The new concept of amortisation could be used as a guideline for the further development of income tax regulation.