《今后25年政府债务的全球经济全景对经济政策及公共政策的启示》.docx

1、今后25年政府债务的全球经济全景对经济政策及公共政策的启示The Burden of Debt and Fiscal LimitsHow much debt is “sustainable”? Ultimately, the level of sustainable debt depends not on some abstract formula, but on the willingness of society and government to pay the interest on the debt and to accept the reduction in GDP caused

2、by the higher interest rates and higher tax rates associated with such a burden. There is no automatic way to calculate that effect but some obvious economic and financial norms do apply. The following analysis seeks to apply the lessons of history for understanding likely future developments. We no

3、te that our analysis does not make any strong assumptions about rationality or foresight of either the public or the private sector. However, there is no guarantee that markets or governments will behave the same in the future as they did in the past.债务负担和财政限制多少债务是“合适”的？可持续的债务水平，最终不是取决于一些抽象的公式，而是取决于

4、社会和政府支付债务利率的意愿，及承受因高利率、高税率而导致GDP减少的意愿。没有固定的方法能计算这些影响，但一些著名的经济金融原理可以适用。接下来的的分析旨在吸取历史教训，更好地预测未来。我们认识到，我们的分析没有对公有、私营行业进行任何理性或前瞻性的断定。然而，市场或政府不能保证今后会采取以前的方法。Effect of Debt on Interest Rates and Interest PaymentsTable 3 and figures 711 display effective interest rates on government debt, both past and pro

5、jected. Since 2006, interest rates have fallen in the United States and the euro area, in part because of the economic downturn, which led investors to buy government securities in dollars and euros as a safe haven, and in part because of the trend increase in reserve accumulation by many government

6、s in developing economies. At the same time, rates have risen in Japan because of the end of the quantitative easing policy. In the baseline scenario, interest rates are projected to equal the trend growth rate of nominal GDP in all economies in 2015, roughly consistent with historical average behav

7、ior and the assumption that output will be near its long-run potential. This projection implicitly assumes that developing economies will slow their rapid purchases of bonds in the advanced economies.债务对利率及利息支付的影响 表3和图7-图11显示出政府债务的实际利率和预测利率。自2006年以来，利率在美国和欧元区下跌，部分是因为经济不景气，导致投资者用美元和欧元购买政府债券作为“避风港”；还有

8、部分原因是许多发展中国家政府外储增加。与此同时，随着量化宽松政策的结束，日本利率上升。基准情形下，假设GDP产量与历史平均水平一致，且达到其长期潜能，到2015年，我们预计利率将与名义GDP增长率趋于一致。该预测无疑假定了发展中国家将放缓购买发达国家债券。What is significant is that beyond 2015, interest rates gradually rise in line with net debt ratios. The cumulative increase is most notable in the United States and Japan,

9、 where rates are at very low levels at present, but it is also significant in Europe. The projected levels of interest rates in 2035 may seem rather modest given the large increases in government debt in some regions. Three factors explain this muted rise in interest rates.2015年以后，利率上调幅度和净负债比率的密切关系将

10、更为显著。虽然在美国和日本，利率目前处于低水平，但利率的累积增长却最为明显，同时对欧洲也适用。到2035年，政府债务大幅度增长的国家利率水平较为适度。三个因素可以解释利率缓慢上升趋势。First, and perhaps most important, our estimates of the effect of government debt on interest rates essentially assume that there is no risk of default. This assumption is appropriate for governments that bor

11、row in currencies they control because they can print money to pay their debts in extremity. The United States, the euro area as a whole, Japan, most other advanced economies, and some emerging economies borrow in currencies they control. But individual euro-area countries and many emerging economie

12、s borrow in currencies they do not control; in such cases, default becomes a serious risk when debt levels rise. A number of studies have found large effects of debt on interest rates for governments that borrow in currencies they do not control. 首先，也是最重要的，在假定没有违约风险的基础上，我们就利率对政府债务的影响进行估计。这种假设是基于，政府能

13、借用他们所控制的货币，最终可以通过印发钞票来支付债务。在美国、欧元区、日本、许多其他经济发达国家，还有一些新兴经济体都借用其所掌控的货币。但是，欧元区的个别国家和许多新兴经济体借用的不是其所控制的货币；在这种情况下，当债务水平上升时，违约将成为一个严重的风险。研究表明，当政府借用不能控制的货币时，利息对债务产生很大的影响。23Second, all of our scenarios assume constant low inflation and stable inflation expectations. There is no way of predicting how future f

14、iscal developments would affect inflation and prices, but the behavior of central banks over the past 20 years suggests that there is a reasonable chance that inflation may remain low even with large increases in debt. At some point, however, increases in the cost of servicing debt are bound to forc

15、e governments to resort to inflationary money creation. If inflation were to increase significantly, interest rates would surely be even higher than projected here. But the real rate of interest (i.e., the nominal interest rate minus the expected inflation rate) might move by an amount consistent wi

16、th the empirical results in table 3. Higher real rates of interest are the primary channel through which government budget deficits crowd out productive investment and ultimately reduce the growth rate of the economy.其次，我们假设持续的低通货膨胀和稳定的通胀预期。目前，无法预测财政前景会如何影响通货膨胀和价格，但央行过去20年的经验表明，即使大幅增加债务，保持低通货膨胀也是有可能

17、的。然而，某些时候，偿债成本的增加势必迫使政府诉诸超发货币。如果通货膨胀大幅增长，利率会比预计高。但是，实际利率（即名义利率减预计通货膨胀率）会有一些变化，这与表3的研究结果一致。更高的实际利率通过政府预算赤字挤出有效投资，从而最终影响经济的增长。图3 政府债务的的有效利率（百分比） 美国乐观增长基线悲观增长悲观的健康代价高利率 欧洲地区同上 日本同上 经济发达国家同上 经济新兴国家同上来源：作者的计算、2005年14期国际货币基金组织的财政数据和预测图7 美国综合政府债券的有效利率基线悲观增长悲观健康高利率低利率乐观增长 来源：作者的计算、2005年14期国际货币基金组织的财政数据和预测Th

18、e third, and probably least important, factor is that in our scenarios the increase in government debt restrains the growth of GDP, which holds down interest rates. This factor becomes significant only in the final few years of the more extreme scenarios.第三，在我们的方案中，或许最不重要的因素是不断增长的政府债务抑制了GDP的增长，同时也阻止

19、了利率的增长。这一因素只有在出现极端情况的最后几年才会变得重要。Table 4 and figures 12-16 display net debt Interest payments as a percent of GDP in each economy. Except for the optimistic growth scenario in the euro area and the emerging markets, interest payments are rising in all economies under all scenarios. Net debt interest

20、payments rise most dramatically in Japan, reflecting the larger growth of debt projected for Japan.表4和图12-16反映了各经济体的净债务利息支出占GDP比例。除欧元区和新兴市场乐观的增长情况外，其他各经济体利息支出是全方位不断上升的。日本净债务利息支出上升最为明显，表明将会出现更大的债务增长。图8 一般政府债务的实际利率-日本基准线悲观增长悲观正常高利率低利率积极增长来源：作者的计算和IMF(国际货币基金组织)官方预测数据2005-14。The Limits of DebtA sovereig

21、n default by the United States or a major country in Europe is obviously unthinkable for policymakers. Nevertheless, markets can react to the possibility of such an occurrence in the long-term future. It is extremely difficult to lay down a hard and fast rule on the limits of borrowing, and the pros

22、pect for default, for economies in the modern era. Reinhart, Rogoff, and Savastano (2003)in their study of the history of borrowing and default around the world, with a particular focus on emerging economieshave shown that economies differ sharply in the levels of debt that governments have tolerate

23、d without default. The question for the future is whether markets will continue to be more worried about a given level of debt in emerging economies than the same level of debt in advanced economies. In many emerging economies, the debt ratios at which defaults have occurred are much lower than the

24、debt ratios that many advanced economies have sustained for decades.债务阈值美国或欧洲主要国家的主权违约对于政策决策者来说显然是不可想象的。不过，市场将对未来可能的违约做出反应。在现代经济体系中，制定对借贷限制和预期违约的硬性规定是非常困难的。莱因哈特，罗格夫和塞瓦斯丹诺（2003年）在其对世界各地特别是新兴经济体的借贷和违约历史的研究表明，在没有违约的情况下，各国政府对债务水平的容忍各不相同。未来的问题是，在一个给定的债务水平上，与发达经济体相比，市场是否仍需更多的担忧新兴经济体。近几十年来，许多新兴经济体的债务违约发生率远

25、低于发达经济体。图9 一般政府债务的实际利率-欧元区基准线悲观增长悲观正常高利率低利率积极增长来源：作者的计算和IMF(国际货币基金组织)官方预测数据2005-14These differences in “debt intolerance” reflect the quality of institutions and the political dynamics in each economy. Reinhart, Rogoff, and Savastano argue that changes in debt intolerance happen only slowly; they po

26、int to Brazil and Chile as examples of economies with rising abilities to bear debt. Of particular interest in light of this years fiscal stresses in Europe, they find that Greece has the lowest debt tolerance of the advanced economies covered by their study.在“债务不耐”上的这些差异反映了各经济体的机构质量和政治动态。莱因哈特，罗格夫和塞

27、瓦斯丹诺认为，“债务不耐”会发生缓慢变化，巴西和智利是经济体中债务承担能力不断增强的例子。根据对今年欧洲财政压力的的关注，他们发现希腊是发达经济体中债务容忍程度最低的。 Ostry et al. (2010) seek to find the limits to the “tolerance” of debt in a sample of advanced economies. For each country, the estimated limit is based on the responsiveness of its fiscal policy to past changes in

28、the level of debt. Not surprisingly, countries with a record of addressing their past problems of deficits and debts are able to run up large amounts of debt without a financial crisis. The results differ moderately across economies, but Ostry et al. find that debt ratios of around 200 percent of GD

29、P are at the extreme limit of what advanced economies can experience without becoming destabilized .24 Their model, however, assumes that financial markets tolerate this level debt primarily because they expect governments to take actions to reduce the burden in the future. Thus, the maximum sustain

30、able level of debt is considably lower than 200 percent of GDP.奥斯特伊（2010）试图在发达经济体中寻求债务“容忍”的限额。每个国家的债务阈值是基于财政政策对以往债务水平变化的反应基础上的。毫无疑问，每个国家都有解决赤字和债务问题的经验，能使其能持有大量的债务而不会发生金融危机。这些结果不同程度地适用于各经济体，但奥斯特伊等发现债务占GDP的 200%左右是发达经济体维持稳定可以承受的极限。24 然而，他们的模型是假设金融市场承受这个债务水平，主要是因为他们期望政府采取行动以减少在未来的负担。因此，最大的可持续债务水平是低于GDP

31、的200%。图10 一般政府债务的实际利率-发达经济体基准线悲观增长悲观正常高利率低利率积极增长来源：作者的计算和IMF(国际货币基金组织)官方预测数据2005-14A simple test of the plausibility of these estimated debt limits is to compare them to the historical intervals when maximum temporary and sustained debt ratios were incurred but without the expectation of default or

32、high ination25. One obvious case of such tolerance is a time of war. Source: Author calculations and IMF fiscal data and projections for 200514. According to CBO (2010b), US federal net debt peaked at just over 100 percent of GDP in 1945, at the close of World War II, and then declined steeply. According to Mares (2010), UK public sector net debt peaked at roughly 250 percent of GDP at the ends of the Napoleonic Wars and World War II and declined steeply after each episode. According to Reinhart (2010) the N