This article surveys the literature on sovereign debt sustainability from its origins in the mid-1980s to the present and focuses on four debates. First, we evaluate the shift from an accounting-based view of debt sustainability using government borrowing rates to a model-based view that uses stochastic discount rates. Second, we review empirical tests, focusing on the relationship between primary balances and debt. Third, we discuss debt sustainability in the presence of rollover risk. And fourth, we evaluate whether government borrowing costs below rates of growth ( r < g) generate a free lunch, in the sense that debt sustainability does not require future primary surpluses. We argue that liquidity services provided by sovereign debt may indeed lead to a free lunch, albeit one of limited size. The value of such services depends on the credibility of the central bank, which can be accumulated via prudent policies and subsequently drawn on to allow for looser fiscal policy. Expected final online publication date for the Annual Review of Financial Economics, Volume 13 is November 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

中文翻译：

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主权债务可持续性和中央银行信誉

本文调查了从 1980 年代中期到现在关于主权债务可持续性的文献，并重点讨论了四个争论。首先，我们评估了从使用政府借款利率的基于会计的债务可持续性观点到使用随机贴现率的基于模型的观点的转变。其次，我们回顾了实证检验，重点关注初级余额和债务之间的关系。第三，我们讨论了存在展期风险的债务可持续性。第四，我们评估低于增长率 (r < g) 的政府借贷成本是否会产生免费午餐，因为债务可持续性不需要未来的初级盈余。我们认为，主权债务提供的流动性服务确实可能带来免费午餐，尽管规模有限。此类服务的价值取决于中央银行的信誉，可以通过审慎的政策积累并随后利用这些信誉来实施更宽松的财政政策。《金融经济学年度评论》第 13 卷的预计最终在线出版日期为 2022 年 11 月。有关修订后的估计，请参阅 http://www.annualreviews.org/page/journal/pubdates。