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For release on delivery
7:00 p.m. EDT
October 14, 1999

Remarks by
Alan Greenspan
Chairman
Board of Governors of the Federal Reserve System
before a
conference sponsored by the
Office of the Comptroller of the Currency
on
Measuring Financial Risk in the Twenty-first Century
Washington, D.C.
October 14, 1999

One of the broad issues that you have been discussing today is the nature of
financial risk. This evening I will offer my perspective on the fundamental sources of
financial risk and the value added of banks and other financial intermediaries. Then, from
that perspective, I will delve into some of the pitfalls inherent in risk-management models
and the challenges they pose for risk managers.
Risk, to state the obvious, is inherent in all business and financial activity.
Its evaluation is a key element in all estimates of wealth. We are uncertain that any
particular nonfinancial asset will be productive. We're also uncertain about the flow of
returns that the asset might engender. In the face of these uncertainties, we endeavor to
estimate the most likely long-term earnings path and the potential for actual results to
deviate from that path, that is, the asset's risk. History suggests that day-to-day movements
in asset values primarily reflect asset-specific uncertainties, but, especially at the portfolio
level, changes in values are also driven by perceptions of uncertainties relating to the
economy as a whole and to asset values generally. These perceptions of broad uncertainties
are embodied in the discount factors that convert the expectations of future earnings to
current present values, or wealth.
In a market economy, all risks derive from the risks of holding real assets or,
equivalently, unleveraged equity claims on those assets. All debt instruments (and, indeed,
equities too) are essentially combinations of long and short positions in those real assets.
The marvel of financial intermediation is that, although it cannot alter the underlying risk in
holding direct claims on real assets, it can redistribute risks in a manner that alters behavior.
The redistribution of risk induces more investment in real assets and hence engenders higher
standards of living.

This occurs because financial intermediation facilitates diversification of risk and
its redistribution among people with different attitudes toward risk. Any means that shifts
risk from those who choose to withdraw from it to those more willing to take it on permits
increased investment without significantly raising the perceived degree of discomfort from
risk that the population overall experiences.
Indeed, all value added from new financial instruments derives from the service
of reallocating risk in a manner that makes risk more tolerable. Insurance, of course, is the
purest form of this service. All the new financial products that have been created in recent
years, financial derivatives being in the forefront, contribute economic value by unbundling
risks and reallocating them in a highly calibrated manner. The rising share of finance in the
business output of the United States and other countries is a measure of the economic value
added from its ability to enhance the process of wealth creation.
But while financial intermediation, through its impetus to diversification, can
lower the risks of holding claims on real assets, it cannot alter the more deep-seated
uncertainties inherent in the human evaluation process. There is little in our historical annals
that suggests that human nature has changed much over the generations. But, as
I have noted previously, while time preference may appear to be relatively stable over
history, perceptions of risk and uncertainty, which couple with time preference to create
discount factors, obviously vary widely, as does liquidity preference, itself a function of
uncertainty. These uncertainties are an underlying source of risk that we too often have
regarded as background noise and generally have not endeavored to capture in our risk
models.
Almost always this has been the right judgment. However, the decline in recent
years in the equity premium—the margin by which the implied rate of discount on common

stock exceeds the riskless rate of interest—should prompt careful consideration of the
robustness of our portfolio risk-management models in the event this judgment proves
wrong.
The key question is whether the recent decline in equity premiums is permanent
or temporary. If the decline is permanent, portfolio risk managers need not spend much time
revisiting a history that is unlikely to repeat itself. But if it proves temporary, portfolio risk
managers could find that they are underestimating the credit risk of individual loans based on
the market value of assets and overestimating the benefits of portfolio diversification.
There can be little doubt that the dramatic improvements in information
technology in recent years have altered our approach to risk. Some analysts perceive that
information technology has permanently lowered equity premiums and, hence, permanently
raised the prices of the collateral that underlies all financial assets.
The reason, of course, is that information is critical to the evaluation of risk. The
less that is known about the current state of a market or a venture, the less the ability to
project future outcomes and, hence, the more those potential outcomes will be discounted.
The rise in the availability of real-time information has reduced the uncertainties
and thereby lowered the variances that we employ to guide portfolio decisions. At least part
of the observed fall in equity premiums in our economy and others over the past five years
does not appear to be the result of ephemeral changes in perceptions. It is presumably the
result of a permanent technology-driven increase in information availability, which by
definition reduces uncertainty and therefore risk premiums. This decline is most evident in
equity risk premiums. It is less clear in the corporate bond market, where relative supplies of
corporate and Treasury bonds and other factors we cannot easily identify have outweighed
the effects of more readily available information about borrowers.

The marked increase over this decade in the projected slope of technology
advance, of course, has also augmented expectations of earnings growth, as evidenced by the
dramatic increase since 1995 in security analysts' projections of long-term earnings. While it
may be that the expectations of higher earnings embodied in equity values have had a
spillover effect on discount factors, the latter remain essentially independent of the earnings
expectations themselves.
That equity premiums have generally declined during the past decade is not in
dispute. What is at issue is how much of the decline reflects new, irreversible technologies,
and what part is a consequence of a prolonged business expansion without a significant
period of adjustment. The business expansion is, of course, reversible, whereas the
technological advancements presumably are not.
Some analysts have offered an entirely different interpretation of the drop in
equity premiums. They assert that a long history of a rate of return on equity persistently
exceeding the riskless rate of interest is bound to induce a learning-curve response that will
eventually close the gap. According to this argument, much, possibly all, of the decline in
equity premiums over the past five years reflects this learning response.
It would be a mistake to dismiss such notions out of hand. We have learned to no longer
cower at an eclipse of the sun or to run for cover at the sight of a newfangled automobile.
But are we really observing in today's low equity premiums a permanent move
up the learning curve in response to decades of data? Or are other factors at play? Some
analysts have suggested several problems with the learning curve argument. One is the
persistence of an equity premium in the face of the history of "excess" equity returns.

Is it possible that responses toward risk are more akin to claustrophobia than to a learning
response? No matter how many times one emerges unscathed from a claustrophobic
experience, the sensitivity remains. In that case, there is no learning experience.
Whichever case applies, what is certain is that the question of the permanence of
the decline in equity premiums is of critical importance to risk managers. They cannot be
agnostic on this question because any abrupt rise in equity premiums must inevitably
produce declines in the values of most private financial obligations. Thus, however clearly
they may be able to evaluate asset-specific risk, they must be careful not to overlook the
possibilities of macro risk that could undermine the value of even a seemingly welldiversified portfolio.
I have called attention to this risk-management challenge in a different context
when discussing the roots of the international financial crises of the past two and a half
years. My focus has been on the perils of risk management when periodic crises—read
sharply rising risk premiums—undermine risk-management structures that fail to address
them.
During a financial crisis, risk aversion rises dramatically, and deliberate trading
strategies are replaced by rising fear-induced disengagement. Yield spreads on relatively
risky assets widen dramatically. In the more extreme manifestation, the inability to
differentiate among degrees of risk drives trading strategies to ever-more-liquid instruments
that permit investors to immediately reverse decisions at minimum cost should that be
required. As a consequence, even among riskless assets, such as U.S. Treasury securities,
liquidity premiums rise sharply as investors seek the heavily traded "on-the-run" issues—a
behavior that was so evident last fall.

As I have indicated on previous occasions, history tells us that sharp reversals in
confidence occur abruptly, most often with little advance notice. These reversals can be
self-reinforcing processes that can compress sizable adjustments into a very short period.
Panic reactions in the market are characterized by dramatic shifts in behavior that are
intended to minimize short-term losses. Claims on far-distant future values are discounted
to insignificance. What is so intriguing, as I noted earlier, is that this type of behavior has
characterized human interaction with little appreciable change over the generations.
Whether Dutch tulip bulbs or Russian equities, the market price patterns remain much the
same.
We can readily describe this process, but, to date, economists have been unable to
anticipate sharp reversals in confidence. Collapsing confidence is generally described as a
bursting bubble, an event incontrovertibly evident only in retrospect.
To anticipate a bubble about to burst requires the forecast of a plunge in the prices of assets
previously set by the judgments of millions of investors, many of whom are highly
knowledgeable about the prospects for the specific investments that make up our broad price
indexes of stocks and other assets.
Nevertheless, if episodic recurrences of ruptured confidence are integral to the
way our economy and our financial markets work now and in the future, the implications for
risk measurement and risk management are significant.
Probability distributions estimated largely, or exclusively, over cycles that do not
include periods of panic will underestimate the likelihood of extreme price movements
because they fail to capture a secondary peak at the extreme negative tail that reflects the
probability of occurrence of a panic. Furthermore, joint distributions estimated over periods
that do not include panics will underestimate correlations between asset returns during

panics. Under these circumstances, fear and disengagement on the part of investors holding
net long positions often lead to simultaneous declines in the values of private obligations, as
investors no longer realistically differentiate among degrees of risk and liquidity, and to
increases in the values of riskless government securities. Consequently, the benefits of
portfolio diversification will tend to be overestimated when the rare panic periods are not
taken into account.
The uncertainties inherent in valuations of assets and the potential for abrupt
changes in perceptions of those uncertainties clearly must be adjudged by risk managers at
banks and other financial intermediaries. At a minimum, risk managers need to stress test
the assumptions underlying their models and set aside somewhat higher contingency
resources—reserves or capital—to cover the losses that will inevitably emerge from time to
time when investors suffer a loss of confidence. These reserves will appear almost all the
time to be a suboptimal use of capital. So do fire insurance premiums.
More important, boards of directors, senior managers, and supervisory authorities
need to balance emphasis on risk models that essentially have only dimly perceived sampling
characteristics with emphasis on the skills, experience, and judgment of the people who have
to apply those models. Being able to judge which structural model best describes the forces
driving asset pricing in any particular period is itself priceless. To paraphrase my former
colleague Jerry Corrigan, the advent of sophisticated risk models has not made people with
grey hair, or none, wholly obsolete.