Mobility, Budget Rules and Government Spending

在过去的几年里，美国联邦政府和州政府都面临着非常相似的预算短缺，但他们的应对方式却截然不同。当联邦政府实施减税并大幅增加支出时，大多数州却恰恰相反。这种明显的差异在很大程度上是由于一项宪法条款，该条款严格限制借贷，除非为持久的改善提供资金。这项条款被大多数州采用，但在美国宪法中却没有。这一条款通常被称为“黄金法则”，被视为将纳税人和政府服务接受者的身份统一起来的一种方式。对于一般费用，受益人主要是当代人，因此需要预算平衡，这要求用当期税收收入提供资金；对于资本改善，收益会溢出到子孙后代，这可以通过发行债券来支付。但是，在州一级而不是在联邦一级证明黄金法则是正当的吗？这条规定对各州来说是一种不必要的束缚，会导致政府规模出现严重而痛苦的波动吗？还是说，在联邦层面上缺乏这种能力，会刺激政府增加巨额赤字，将税收负担转嫁给后代？或者是否存在在一个上下文中采用规则而在另一个上下文中不采用规则的理由？该项目开发了一个动态的政治经济模型来定量研究不同预算规则的执行情况。在该模型中，不同年龄的个人根据宪法规定的融资规则，对政府部门的规模和组成进行投票。在进行个人选择和投票时，个人会考虑当前政策选择对未来经济发展道路的影响。在个人对公共投资的偏好中，跨税收管辖区的流动性起着关键作用。例如，美国居民在某一年中迁出美国的概率远低于他/她在该年死亡的概率。相比之下，年轻人和中年人每年跨越州界的概率大约是他们死亡概率的10倍。这种明显的差异意味着，在这两种情况下，当代人和后代之间的冲突具有非常不同的含义，这意味着州和联邦层面的不同财政机构可能是有必要的。最近出现的联邦赤字很可能会重新引发对年度预算程序施加限制以确保财政纪律的辩论，以及对美国宪法平衡预算修正案的适当性的辩论。类似的争论在欧盟已经非常活跃，欧盟的《欧洲稳定公约》（European Stability Pact）（至少在原则上）对赤字支出施加了严格的限制，却没有区分赤字支出的不同类别。本项目提出的分析将非常有价值，有助于对此类财政机构的设计做出明智的决策。

In the last couple of years, the U.S. federal government and the state governments have faced very similar budget shortfalls, but they have reacted to them in radically different ways. While the federal government enacted tax cuts and significantly increased its spending, most states have done exactly the opposite. The stark difference is in large part due to a constitutional provision, adopted by most states but absent from the U.S.Constitution, that severely restricts borrowing, except to finance lasting improvements.This provision, commonly known as the golden rule, has been seen as a way of aligning the identities of the taxpayers and the recipients of government services. For ordinary expenses, beneficiaries are mainly current generations, hence the requirement of budget balance, which mandates funding with contemporaneous tax receipts; for capital improvements, benefits spill over to future generations, that can be made to pay by issuing debt. But what justifies the golden rule at the state level and not at the federal level? Is this rule a needless straitjacket for the states, that causes severe and painful fluctuations in the size of their government? Or is its lack at the federal level an incentive to run large deficits, shifting the burden of taxes onto future generations? Or is there a rationale for adopting the rule in one context, but not in the other? This project develops a dynamic, politico-economic model to study quantitatively the performance of different budget rules. In the model, individuals of different ages vote over the size and composition of the government sector, subject to the financing rules laid out in the constitution. In making their private choices as well as in casting their votes, individuals take into account the repercussions of current policy choices on the future path of the economy. A key role in an individual's preferences over public investment is played by mobility across tax jurisdictions. As an example, the probability that a U.S. resident will move out of the country in any given year is much lower than his/her probability of death in the same year. By contrast, young and middle-age people face a yearly probability of moving across state lines that is about 10 times as high as their probability of death. This stark difference implies that the conflict between current and future generations has a very different meaning in the two cases, and it implies that different fiscal institutions at the state and federal level may be warranted.The recent resurgence of the federal deficit is likely to rekindle the debate on the restrictions that should be imposed on the yearly budgeting process to insure fiscal discipline, and on the appropriateness of a balanced-budget amendment to the U.S. Constitution. A similar debate is already very lively in the European Union, where the European Stability Pact imposes (in principle, at least) tight bounds to deficit spending, without distinguishing between its different categories. The analysis proposed in this project will be very valuable in making informed decisions on the design of such fiscal institutions.