Monthly return on hedge fund indexes versus return on the S&P 500, 2008–2012. Panel A,
hedge fund index. Panel B, market-neutral funds. Panel C, short-bias funds.
C H A P T E R
2 6
Hedge
Funds
943
with black swans, deeply important developments that simply could not have been predicted
from the range of accumulated experience to date. While we can’t predict which black swans
to expect, we nevertheless know that some black swan may be making an appearance at any
moment. The October 1987 crash, when the market fell by more than 20% in 1 day, might be
viewed as a black swan—an event that had never taken place before, one that most market
observers would have dismissed as impossible and certainly not worth modeling, but with
high impact. These sorts of events seemingly come out of the blue, and they caution us to
show great humility when we use past experience to evaluate the future risk of our actions.
With this in mind, consider again the example of Long Term Capital Management.
In the late 1990s, Long Term Capital Management was widely viewed as the most
successful hedge fund in history. It had consistently provided double-digit returns to
its investors, and it had earned hundreds of millions of dollars in incentive fees for its
managers. The firm used sophisticated computer models to estimate correlations across
assets and believed that its capital was almost 10 times the annual standard deviation of
its portfolio returns, presumably enough to withstand any “possible” shock to capital (at
least, assuming normal distributions!). But in the summer of 1998, things went badly.
On August 17, 1998, Russia defaulted on its sovereign debt and threw capital markets
into chaos. LTCM’s 1-day loss on August 21 was $550 million (approximately nine times
its estimated monthly standard deviation). Total losses in August were about $1.3 bil-
lion, despite the fact that LTCM believed that most of its positions were market-neutral
relative-value trades. Losses accrued on virtually all of its positions, flying in the face of
the presumed diversification of the overall portfolio.
How did this happen? The answer lies in the massive flight to quality and, even
more so, to liquidity that was set off by the Russian default. LTCM was typically a seller
of liquidity (holding less liquid assets, selling more liquid assets with lower yields, and
earning the yield spread) and suffered huge losses. This was a different type of shock
from those that appeared in its historical sample/modeling period. In the liquidity crisis
that engulfed asset markets, the unexpected commonality of liquidity risk across usually
uncorrelated asset classes became obvious. Losses that seemed statistically impossible
on past experience had in fact come to pass; LTCM fell victim to a black swan.
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