양도소득세제 변화에 따른 주택시장 분석 : system dynamics를 이용한 주택시장의 장기예측모형을 중심으로

양도소득세제 변화가 주택시장에 미치는 영향을 분석했다.

This study aimed to examine the effect of housing price measurement using capital gains tax system by the government in the housing market. Different from statistical and quantitative analysis for price effect analysis assumed single relation by most existing researchers, this study adopted System Dynamics method in terms of complex system theory to figure out factors intended or not intended in the policy making by the government. Theoretical investigation and review of previous studies were carried out through various literature resources and regulations. It was followed by the collection of statistical data to figure out the trend of housing market and capital gains tax system.

Then, the study prepared a cognitive map of the effect of capital gains tax system change upon the housing market. Based on it, the relation of various factors in the housing market was examined using System Dynamics and the study prepared causal loop diagram and stock-flow diagram to make comprehensive analysis of dynamic change of influence against other factors in order to establish long-term estimation model of the housing market. And simulation analysis was performed using an established model.

3-level scenario toward ratio subject to capital gains taxation was set, and to reflect future housing price increase, the variable of cognitive housing price increase was used to add to 3-level scenario. So, total 6-level scenarios were set to perform a mock test. As a result of simulation analysis, the change of capital gains tax system used to operate as cause of short-term market recession which was contrary to the intention of the government. It is conjectured that lock-in effect of supply worked as a cause of market failure contrary to the policy. In particular, ht had almost no stability effect of housing price in the long term.

The causes of long-term policy failure as well as short-term market failure, includes, firstly the percentage of subject of capital gains tax. About 77.5% of the housing transaction had non-taxation or tax-exemption of capital gains tax. Thus, about 22.5% was the subject of capital gains tax. It means that when housing market control policy is performed using capital gains tax system, only 22.5% is subject to the influence. In particular, the percentage of subject to heavy taxation with 1 household with more than 2 houses is nothing but 11.5%.

As such, the subject of capital gains tax system measurement was very limited, and heavy taxation or reduced taxation of capital gains tax has restricted effect only. This was confirmed by the scenario analysis that the more increase of subject of taxation of capital gains tax caused the higher price variation. Secondly, as capital gains tax system is a tax imposed to capital profit, if nominal value of capital does not increase to a certain degree, it generates no capital gains because of no gains on transfer. This indicates it has effects in the market where capital profit keeps high continually.

Potential consumers who have expectation of increase of future housing price to a certain level might participate in the purchase with an expectation of capital profit by the expected gain against the capital gains tax reduction as the government intends. However, if potential consumers recognize future housing price would recess as in the capital housing market the reduction policy of capital gains tax by the government could not but be insignificant. In conclusion, the government failed to consider the scope of subject influenced because of the weakness that scope of non-taxation or exemption of taxation was too extensive when implementing the policy through capital gains tax system.

And the government overlooked the fact that consumers’ expectation of change of future housing price plays a core role in the housing market. As a result, the housing price stabilized policy through capital gains tax system continues to be failure. Currently, existing unrealizable policies are repeated in the housing market. As tax has direct influence on decision making of the economic subject, many countries carry out various economic policies using the control of taxation. However, while there are some effects through tax policies, there are also cases with no effect.

To attract the housing market to the direction the government wants to lead to, the government imposes heavy capital gains tax or reduces burden of the tax. That is to say, the government intended to control the housing market through capital gains tax system. However, as shown in this study, it had almost no long-term or short-term effect and caused side-effects. The capital gains tax system operation method in the past or current is not desirable and is not sustainable in terms of effect.

Accordingly, it is recommended that capital gains tax system must not be abused for any other purpose than financial function as tax or social equality function like return of essential development profit.