A global perspective on the great financial insurance run: Causes, consequences, and solutions (Part 1)

Ricardo Caballero 23 January 2009



This is a financial crisis to remember. The financial losses are measured in trillions of dollars; elite financial institutions have fallen; fear and mistrust are widespread among investors and lenders; credit markets are not operating except for those with very short maturities; massive and unorthodox policy interventions are an every day occurrence; and we have been, and continue to be, on the verge of a global financial meltdown.

How did we get into this situation? What should we do to get out of it and to prevent a relapse?

This pair of Vox columns addresses these questions, suggesting that the consensus view of the crisis’s causes and cures is flawed. (These columns are based on a talk at MIT’s 20 January 2009 Economics Alumni dinner in New York City.)

The emerging consensus

There is an emerging consensus on the causes of the crisis, which essentially rehashes an old list of complaints about potential excesses committed in the phase prior to the crisis. The sins include uncontrolled global imbalances, unscrupulous lenders, and an insatiable Wall Street, all of them lubricated by an ever-expansionary Federal Reserve.

It follows from this perspective that the appropriate policy response is to focus on reducing global imbalances, boosting financial regulation, bringing down leverage ratios, and adding bubble-control to the Fed’s mandate.

I do not share this consensus view and its policy prescriptions.

The rest of this column develops my view of the crisis’s causes. I start with the pre-crisis phase and then portray the current crisis as primarily a run on all forms of private insurance.

My second column discusses optimal economic policy in this environment.

The pre-crisis phase: Global excess demand for safe assets

For quite some time, but in particular since the late 1990s, the world has experienced a chronic shortage of financial assets to store value. The reasons behind this shortage are varied. They include the rise in savings needs by aging populations in Japan and Europe, the fast growth and global integration of high-saving economies, the precautionary response of emerging markets to earlier financial crises, and the intertemporal smoothing of commodity producing economies.

The immediate consequence of the high demand for store-of-value instruments was a sustained decline in real interest rates. Conventional wisdom blames these low rates on loose monetary policy, but this position is difficult to reconcile with facts from the period of the so-called “Greenspan conundrum’’ – when tightening monetary policy had virtually no impact on long rates. In my view, the solution to the apparent conundrum is that low long rates were driven by the large demand for store-of-value instruments, not short-term monetary policy considerations.

Global imbalances were created by the demand for safe US assets

Low real interest rates are an equilibrium response by which the market creates value out of existing financial assets. Yet another mechanism to increase asset supply is the creation of new assets, including the emergence of the many speculative bubbles that we have seen over the last decade (some of which are legal and some are not – e.g., the NASDAQ bubble and the Madoff scheme, respectively).

Moreover, because of the US’s role as the centre of world capital markets, much of the large global demand for financial assets has been channelled toward US assets. This has been the main reason for the large global “imbalances” observed in recent years. The large current account deficits experienced by the US are simply the counterpart of the large demand for its assets.

How the subprime mortgage market fits in

Under this perspective, there is a more subtle angle on subprime mortgages than simply being the result of unscrupulous lenders. The world needed more assets and the subprime mortgages were helping to bridge the gap. So far, so good.

However, there was one important caveat that would prove crucial later on. The global demand for assets was particularly for very safe assets – assets with AAA credit ratings. This is not surprising in light of the importance of central banks and sovereign wealth funds in creating this high demand for assets. Moreover, this trend toward safety became even more pronounced after the NASDAQ crash.

Soon enough, US banks found a “solution” to this mismatch between the demand for safe assets and the expansion of supply through the creation of risky subprime assets – the market moved to create synthetic AAA instruments. This consisted of pooling subprime mortgages on the asset side of a Structured Investment Vehicle (SIV), and to tranche (slice) the liability side to generate a AAA component buffered by the now ultra-volatile “toxic” residual. The latter was then pooled again into Collateralized Debt Obligations (CDOs), tranched again, and then into CDO-squared, and so on. At the end of this iterative process, many new AAA assets were produced out of some very risky subprime mortgages.

Safe and risky tranches: An accident waiting to happen

The AAA tranches so created were held by the non-levered sector of the world economy, including central banks, sovereign wealth funds, pension funds, etc. They were also held by a segment of the highly-levered sector, especially foreign banks and domestic banks that kept them on their books, directly and indirectly, as they provided attractive “safe” yields. The small toxic component was mostly held by agents that could handle the risk, although highly levered investment banks also were exposed.

Much of the focus on the regulatory and credit agency mistakes highlights the fact that the AAA tranche seems to have been too large relative to the “true” capacity of the underlying risky instruments to create such a tranche. While I agree with this assessment, I believe it is incomplete and, because of this, it does not point to the optimal policy response.

Individual default risk vs severe macro risk

Instead, I believe the key issue is that even if we give the benefit of the doubt to the credit agencies and accept that these instruments were indeed AAA from an unconditional probability of default perspective (the only one that counts for credit agencies), they were not so with respect to severe macroeconomic risk.

This created a highly volatile concoction where highly levered institutions of systemic importance were holding assets that were very vulnerable to aggregate shocks. This was an accident waiting to happen.

The (insurance) crisis: Triple A turns toxic, fear of the unknown spreads

And happen it did. It started without much fanfare sometime in 2006, limited to the housing sector and the associated subprime mortgage market. Eventually, it spread to the financial sector as the securitisation markets supported by these mortgages and other risky loans began to freeze. As this happened, conventional margin and collateral feedback mechanisms amplified the incipient liquidity problem. Then suddenly, the soundness of the AAA instruments created from risky loans in the previous phase were questioned. In particular, economic agents realised that they didn’t quite understand what was behind these instruments (Caballero and Krishnamurthy 2008a).

This confusion was the first inkling of something that would later ravage global financial markets. Financial institutions specialise in handling risk but are not nearly as efficient in dealing with uncertainty.

Uncertain versus risk

To paraphrase a recent secretary of defence, risk refers to situations where the unknowns are known, while uncertainty refers to situations where the unknowns are unknown. This distinction is not only linguistically interesting, but also has significant implications for economic behaviour and policy prescriptions.

There is extensive experimental evidence that economic agents faced with (Knightian) uncertainty become overly concerned with extreme, even if highly unlikely, negative events. Unfortunately, the very fact that investors behave in this manner make the dreaded scenarios all the more likely.

US Treasury’s uncertain response makes things worse

Worsening the situation, until very recently, the policy response from the US Treasury exacerbated rather than dampened the uncertainty problem.

Early on in the crisis, there was a nagging feeling that policy was behind the curve; then came the “exemplary punishment” (of shareholders) policy of Secretary Paulson during the Bear Stearns intervention, which significantly dented the chance of a private capital solution to the problem; and finally, the most devastating blow came during the failure to support Lehman. The latter unleashed a very different kind of recession, where uncertainty ravaged all forms of explicit and implicit financial insurance markets.

In the next column I discuss what should be done in light of my analysis of the causes of this financial crisis.


Knightian Uncertainty and its Implications for the TARP
Ricardo J. Caballero and Arvind Krisnamurthy
Financial Times, November 24, 2008

Paulson Plan: "Exemplary Punishment" Could Backfire
Ricardo J. Caballero and Pablo Kurlat
Financial Times, The Economists' Forum, Monday, 29 September, 2008

"Musical Chairs.pdf"
Ricardo J. Caballero and Arvind Krishnamurthy
February 2008a

Global Imbalances and Financial Fragility
Ricardo J. Caballero and Arvind Krishnamurthy
December 16, 2008b

Financial Crash, Commodity Prices and Global Imbalances
Ricardo J. Caballero, Emmanuel Farhi, Pierre-Olivier Gourinchas
November 17, 2008  (forthcoming, Brookings Papers on Economic Activity)

Flight to Quality and Bailouts: Policy Remarks and a Literature Review
Ricardo J. Caballero and Pablo Kurlat
October 2008

Collective Risk Management in a Flight to Quality Episode
Ricardo J. Caballero and Arvind Krisnamurthy
Journal of Finance, Vol. 63, Issue 5, October 2008

An Equilibrium Model of "Global Imbalances" and Low Interest Rates

Ricardo J. Caballero, Emmanuel Farhi, and Pierre-Olivier Gourinchas
American Economic Review 2008, 98:1, pgs 358-393.

On the Macroeconomics of Asset Shortages
The Role of Money: Money and Monetary Policy in the Twenty-First Century
The Fourth European Central Banking Conference 9-10 November 2006, Andreas Beyer and Lucrezia Reichlin, editors. Pages 272-283.




Topics:  Financial markets

Tags:  global financial crisis

Professor of Economics, MIT


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