This article reviews the literature on sovereign debt, that is, debt issued by a national government. The defining characteristic of sovereign debt is the limited mechanisms for enforcement. Because a sovereign government does not face legal consequences of default, the reasons why it makes repayment are to avoid default penalties related to reputation loss or economic cost. Theoretical and quantitative studies on sovereign debt have investigated the cause and impact of sovereign default and produced analysis of policy relevance. This article reviews the theories that quantitatively account for key empirical facts about sovereign debt. These studies enable researchers and policy makers to better understand sovereign debt crises.
Vivian Zhanwei Yue and Bin Wei
Carlos Garriga and Aaron Hedlund
The global financial crisis of 2007–2009 helped usher in a stronger consensus about the central role that housing plays in shaping economic activity, particularly during large boom and bust episodes. The latest research regards the causes, consequences, and policy implications of housing crises with a broad focus that includes empirical and structural analysis, insights from the 2000s experience in the United States, and perspectives from around the globe. Even with the significant degree of heterogeneity in legal environments, institutions, and economic fundamentals over time and across countries, several common themes emerge. Research indicates that fundamentals such as productivity, income, and demographics play an important role in generating sustained movements in house prices. While these forces can also contribute to boom-bust episodes, periods of large house price swings often reflect an evolving housing premium caused by financial innovation and shifts in expectations, which are in turn amplified by changes to the liquidity of homes. Regarding credit, the latest evidence indicates that expansions in lending to marginal borrowers via the subprime market may not be entirely to blame for the run-up in mortgage debt and prices that preceded the 2007–2009 financial crisis. Instead, the expansion in credit manifested by lower mortgage rates was broad-based and caused borrowers across a wide range of incomes and credit scores to dramatically increase their mortgage debt. To whatever extent changing beliefs about future housing appreciation may have contributed to higher realized house price growth in the 2000s, it appears that neither borrowers nor lenders anticipated the subsequent collapse in house prices. However, expectations about future credit conditions—including the prospect of rising interest rates—may have contributed to the downturn. For macroeconomists and those otherwise interested in the broader economic implications of the housing market, a growing body of evidence combining micro data and structural modeling finds that large swings in house prices can produce large disruptions to consumption, the labor market, and output. Central to this transmission is the composition of household balance sheets—not just the amount of net worth, but also how that net worth is allocated between short term liquid assets, illiquid housing wealth, and long-term defaultable mortgage debt. By shaping the incentive to default, foreclosure laws have a profound ex-ante effect on the supply of credit as well as on the ex-post economic response to large shocks that affect households’ degree of financial distress. On the policy front, research finds mixed results for some of the crisis-related interventions implemented in the U.S. while providing guidance for future measures should another housing bust of similar or greater magnitude reoccur. Lessons are also provided for the development of macroprudential policy aimed at preventing such a future crisis without unduly constraining economic performance in good times.
African financial history is often neglected in research on the history of global financial systems, and in its turn research on African financial systems in the past often fails to explore links with the rest of the world. However, African economies and financial systems have been linked to the rest of the world since ancient times. Sub-Saharan Africa was a key supplier of gold used to underpin the monetary systems of Europe and the North from the medieval period through the 19th century. It was West African gold rather than slaves that first brought Europeans to the Atlantic coast of Africa during the early modern period. Within sub-Saharan Africa, currency and credit systems reflected both internal economic and political structures as well as international links. Before the colonial period, indigenous currencies were often tied to particular trades or trade routes. These systems did not immediately cease to exist with the introduction of territorial currencies by colonial governments. Rather, both systems coexisted, often leading to shocks and localized crises during periods of global financial uncertainty. At independence, African governments had to contend with a legacy of financial underdevelopment left from the colonial period. Their efforts to address this have, however, been shaped by global economic trends. Despite recent expansion and innovation, limited financial development remains a hindrance to economic growth.
Florian Exler and Michèle Tertilt
Consumer debt is an important means for consumption smoothing. In the United States, 70% of households own a credit card, and 40% borrow on it. When borrowers cannot (or do not want to) repay their debts, they can declare bankruptcy, which provides additional insurance in tough times. Since the 2000s, up to 1.5% of households declared bankruptcy per year. Clearly, the option to default affects borrowing interest rates in equilibrium. Consequently, when assessing (welfare) consequences of different bankruptcy regimes or providing policy recommendations, structural models with equilibrium default and endogenous interest rates are needed. At the same time, many questions are quantitative in nature: the benefits of a certain bankruptcy regime critically depend on the nature and amount of risk that households bear. Hence, models for normative or positive analysis should quantitatively match some important data moments. Four important empirical patterns are identified: First, since 1950, consumer debt has risen constantly, and it amounted to 25% of disposable income by 2016. Defaults have risen since the 1980s. Interestingly, interest rates remained roughly constant over the same time period. Second, borrowing and default clearly depend on age: both measures exhibit a distinct hump, peaking around 50 years of age. Third, ownership of credit cards and borrowing clearly depend on income: high-income households are more likely to own a credit card and to use it for borrowing. However, this pattern was stronger in the 1980s than in the 2010s. Finally, interest rates became more dispersed over time: the number of observed interest rates more than quadrupled between 1983 and 2016. These data have clear implications for theory: First, considering the importance of age, life cycle models seem most appropriate when modeling consumer debt and default. Second, bankruptcy must be costly to support any debt in equilibrium. While many types of costs are theoretically possible, only partial repayment requirements are able to quantitatively match the data on filings, debt levels, and interest rates simultaneously. Third, to account for the long-run trends in debts, defaults, and interest rates, several quantitative theory models identify a credit expansion along the intensive and extensive margin as the most likely source. This expansion is a consequence of technological advancements. Many of the quantitative macroeconomic models in this literature assess welfare effects of proposed reforms or of granting bankruptcy at all. These welfare consequences critically hinge on the types of risk that households face—because households incur unforeseen expenditures, not-too-stringent bankruptcy laws are typically found to be welfare superior to banning bankruptcy (or making it extremely costly) but also to extremely lax bankruptcy rules. There are very promising opportunities for future research related to consumer debt and default. Newly available data in the United States and internationally, more powerful computational resources allowing for more complex modeling of household balance sheets, and new loan products are just some of many promising avenues.
Murray Z. Frank, Vidhan Goyal, and Tao Shen
The pecking order theory of corporate capital structure developed by states that issuing securities is subject to an adverse selection problem. Managers endowed with private information have incentives to issue overpriced risky securities. But they also understand that issuing such securities will result in a negative price reaction because rational investors, who are at an information disadvantage, will discount the prices of any risky securities the firm issues. Consequently, firms follow a pecking order: use internal resources when possible; if internal funds are inadequate, obtain external debt; external equity is the last resort. Large firms rely significantly on internal finance to meet their needs. External net debt issues finance the minor deficits that remain. Equity is not a significant source of financing for large firms. By contrast, small firms lack sufficient internal resources and obtain external finance. Although much of it is equity, there are substantial issues of debt by small firms. Firms are sorted into three portfolios based on whether they have a surplus or a deficit. About 15% of firm-year observations are in the surplus group. Firms primarily use surpluses to pay down debt. About 56% of firm-year observations are in the balance group. These firms generate internal cash flows that are just about enough to meet their investment and dividend needs. They issue debt, which is just enough to meet their debt repayments. They are relatively inactive in equity markets. About 29% of firm-year observations are in the deficit group. Deficits arise because of a combination of negative profitability and significant investments in both real and financial assets. Some financing patterns in the data are consistent with a pecking order: firms with moderate deficits favor debt issues; firms with very high deficits rely much more on equity than debt. Others are not: many equity-issuing firms do not seem to have entirely used up the debt capacity; some with a surplus issue equity. The theory suggests a sharp discontinuity in financing methods between surplus firms and deficit firms, and another at debt capacity. The literature provides little support for the predicted threshold effects. The theoretical work has shown that adverse selection does not necessarily lead to pecking order behavior. The pecking order is obtained only under special conditions. With both risky debt and equity being issued, there is often scope for many equilibria, and there is no clear basis for selecting among them. A pecking order may or may not emerge from the theory. Several articles show that the adverse selection problem can be solved by certain financing strategies or properly designed managerial contracts and can even disappear in dynamic models. Although adverse selection can generate a pecking order, it can also be caused by agency considerations, transaction costs, tax consideration, or behavioral decision-making considerations. Under standard tests in the literature, these alternative underlying motivations are commonly observationally equivalent.
Hengjie Ai, Murray Z. Frank, and Ali Sanati
The trade-off theory of capital structure says that corporate leverage is determined by balancing the tax-saving benefits of debt against dead-weight costs of bankruptcy. The theory was developed in the early 1970s and despite a number of important challenges, it remains the dominant theory of corporate capital structure. The theory predicts that corporate debt will increase in the risk-free interest rate and if the tax code allows more generous interest rate tax deductions. Debt is decreasing in the deadweight losses in a bankruptcy. The equilibrium price of debt is decreasing in the tax benefits and increasing in the risk-free interest rate. Dynamic trade-off models can be broadly divided into two categories: models that build capital structure into a real options framework with exogenous investments and models with endogeneous investment. These models are relatively flexible, and are generally able to match a range of firm decisions and features of the data, which include the typical leverage ratios of real firms and related data moments. The literature has essentially resolved empirical challenges to the theory based on the low leverage puzzle, profits-leverage puzzle, and speed of target adjustment. As predicted, interest rates and market conditions matter for leverage. There is some evidence of the predicted tax rate and bankruptcy code effects, but it remains challenging to establish tight causal links. Overall, the theory provides a reasonable basis on which to build understanding of capital structure.
The links of international reserves, exchange rates, and monetary policy can be understood through the lens of a modern incarnation of the “impossible trinity” (aka the “trilemma”), based on Mundell and Fleming’s hypothesis that a country may simultaneously choose any two, but not all, of the following three policy goals: monetary independence, exchange rate stability, and financial integration. The original economic trilemma was framed in the 1960s, during the Bretton Woods regime, as a binary choice of two out of the possible three policy goals. However, in the 1990s and 2000s, emerging markets and developing countries found that deeper financial integration comes with growing exposure to financial instability and the increased risk of “sudden stop” of capital inflows and capital flight crises. These crises have been characterized by exchange rate instability triggered by countries’ balance sheet exposure to external hard currency debt—exposures that have propagated banking instabilities and crises. Such events have frequently morphed into deep internal and external debt crises, ending with bailouts of systemic banks and powerful macro players. The resultant domestic debt overhang led to fiscal dominance and a reduction of the scope of monetary policy. With varying lags, these crises induced economic and political changes, in which a growing share of emerging markets and developing countries converged to “in-between” regimes in the trilemma middle range—that is, managed exchange rate flexibility, controlled financial integration, and limited but viable monetary autonomy. Emerging research has validated a modern version of the trilemma: that is, countries face a continuous trilemma trade-off in which a higher trilemma policy goal is “traded off” with a drop in the weighted average of the other two trilemma policy goals. The concerns associated with exposure to financial instability have been addressed by varying configurations of managing public buffers (international reserves, sovereign wealth funds), as well as growing application of macro-prudential measures aimed at inducing systemic players to internalize the impact of their balance sheet exposure on a country’s financial stability. Consequently, the original trilemma has morphed into a quadrilemma, wherein financial stability has been added to the trilemma’s original policy goals. Size does matter, and there is no way for smaller countries to insulate themselves fully from exposure to global cycles and shocks. Yet successful navigation of the open-economy quadrilemma helps in reducing the transmission of external shock to the domestic economy, as well as the costs of domestic shocks. These observations explain the relative resilience of emerging markets—especially in countries with more mature institutions—as they have been buffered by deeper precautionary management of reserves, and greater fiscal and monetary space. We close the discussion noting that the global financial crisis, and the subsequent Eurozone crisis, have shown that no country is immune from exposure to financial instability and from the modern quadrilemma. However, countries with mature institutions, deeper fiscal capabilities, and more fiscal space may substitute the reliance on costly precautionary buffers with bilateral swap lines coordinated among their central banks. While the benefits of such arrangements are clear, they may hinge on the presence and credibility of their fiscal backstop mechanisms, and on curbing the resultant moral hazard. Time will test this credibility, and the degree to which risk-pooling arrangements can be extended to cover the growing share of emerging markets and developing countries.