Abstract
Conversion is basically a problem to be solved by the market. A choice between converting and reconstructing a building and among converting different uses like condominiums, hotel rooms, SOHO's, etc. are both to be left to the market. Here, the administrative intervention must be taken unless there occurs any town or housing problem caused by the market failure.
Discretionary interferences must not be taken because of any ‘policy failure’. Instead, it is strongly recommended to provide market players with social infrastructures to make themselves adapt to the market changes and to minimize unfavorable effects of the policy failure.
For it, enlarging time period for carrying forward of net losses is required in the corporate income tax system. It is not requested as a temporal political tax policy but is essentially needed as a part of the permanent tax system for neutrality and equity of the tax.
