The impact of capital gains taxation on asset prices, realization behavior, and trading volume

Abstract

The lock-in effect discourages investors from switching investments in a portfolio that is no longer optimal. It is possible, however, that the negative impact of the lock-in effect on gain realizations can be offset by the positive impact of capital gains taxes on the demand for risky assets when losses are not subject to special restrictions. While previous studies have examined the impact of the lock-in effect of current capital gains taxes on realization behavior (e.g., Feldstein, Slemrod, and Yitzhaki, 1980; Burman and Randolph, 1994) and the impact of the variance-reduction effect of future capital gains taxes on the demand for risky assets (e.g., Mossin, 1968; Stiglitz, 1969), there is little extant research that analyzes the impact of both current and future capital gains taxes on portfolio composition. This dissertation examines the impact of capital gains taxation on individual investor behavior in a proportional income tax regime. I study this problem using two different approaches. First, I develop a single period general equilibrium model to derive propositions regarding the impact of capital gains taxation on portfolio diversification. Second, I examine the impact of capital gains taxation in a multiperiod experimental asset market similar to the "bubbles" markets described in Smith, Suchanek, and Williams (1988). The experimental results show that realization behavior in markets with constant rate capital gains taxation are not significantly different than that in tax-free markets. Moreover, both analytical and experimental results indicate that capital gains taxation has a significant impact on prices and realization behavior when the tax rate on current capital gains is different than the expected tax rate on future capital gains. These results are consistent with evidence presented in Burman and Randolph (1994) which suggest that the inverse relationship between gain realizations and the capital gains tax rate is driven by temporary differences between current and future tax rates rather than the permanent level of the capital gains tax rate.