Consumption Taxes and Saving: The Role of Uncertainty in Tax Reform
通过一般均衡、世代交叠、随机生命周期模拟模型，分析美国从现行税制转向统一消费税对长期储蓄率的影响，发现储蓄率约提高1个百分点，GDP增长1-2%，但预防性储蓄等因素会削弱这一效果。
The effects of fundamental tax refonn may work through many different avenues, but an important goal is to increase saving. The effect on saving of a switch to a flat-rate consumption tax would be influenced by at least several factors. First, the effect on saving would depend on the magnitude of the tax burden placed on saving in the current system. Second, it would be determined by the response of the rate of return to capital and the sensitivity of saving to changes in its after-tax return. Third, the effect would be contingent upon the redistribution of tax burdens across groups with different propensities to save, including any windfall gains and losses created in the transition to the new system. The uncertainties that households face and the role of precautionary saving are important components for evaluating these issues. These issues are examined using a generalequilibrium, overlapping-generations, stochastic life-cycle simulation model. The existing U.S. tax system is modeled as a progressive tax with a base that is a hybrid between a consumption tax and an income tax. Our simulation results indicate that moving from the existing system to a flat-rate consumption tax would raise the long-term saving rate by approximately I percentage point, and increase GDP by about 1-2 percent in the long run. These results reflect the interaction of several effects. Moving to a consumption-based tax would reduce tax rates on new saving, raising the after-tax return to saving, and would lighten tax burdens on households that save more. These effects would increase saving. But these positive effects on saving would be moderated by several factors. First, the current tax system already taxes a substantial portion of household saving as it would be taxed under a consumption tax. For saving that is tax-preferred in the current system, there is no first-order effect of switching to a consumption-based tax, as it already receives consumption-tax treatment. Second, saving that is done for precautionary reasons is relatively insensitive to the rate of return, so a portion of household saving would be unresponsive to an increase in the after-tax return induced by tax reform. Third, transition rules may eliminate taxes on consumption financed with assets accumulated prior to tax reform. These transition rules would shift some of the tax burden from older cohorts with lower saving propensities to younger cohorts with higher saving propensities, which would further reduce the positive saving effects of switching to a consumption tax.