Lehman's Risk Management Strategy May Have Caused the Problems

When Lehman Brothers Holdings Inc. (LEH) announced a third-quarter loss of $3.9 billion earlier this week, the investment bank’s shares plunged as Wall Street questioned its long-term ability to survive.

Of the five big investment banks that were in operation at the outset of this year, The Bear Stearns Cos. has already failed and been taken over and Lehman Brothers is trying to avoid a similar fate. That leaves only three members of the original group - Goldman Sachs Group Inc. (GS), Merrill Lynch & Co. Inc. (MER) and Morgan Stanley (MS) - a casualty rate as steep as the one experienced by second lieutenants on World War I’s Western Front. And that begs the question: Just where were all the risk-management experts who should have assessed the pitfalls these companies faced, and how could they have missed the massive risks that are now threatening to take this entire sector down?

The answer may be more than a minor exercise in financial irony. Lehman, the latest Wall Street investment bank forced to the brink of failure, may have put itself out on that precipice with its own risk-management strategies.

Let’s take a closer look.

In its 2008 Annual Report, Lehman boasted of having "a culture of risk management at every level of the firm." That was written at the end of last year, when the global stock and credit markets had already been in turmoil for several months. As an investor, one’s question here has to be: "If there was a culture of risk management at every level of the firm, how come you allowed the leverage ratio (total assets divided by stockholders equity) to rise from 26.2 to 1 in the tranquil bull market of 2006, to 30.7 to 1 in the troubled market of November 2007?"

Even more bothersome: There weren’t any losses that year that dinged stockholders’ equity - in fact, Lehman increased its stockholders’ equity by more than $3 billion.

Investment bankers love leverage: That’s because the more assets you control, the more chance you have to make money from them - and the bigger the bonus you can hope for at the end of the year. However, 12 years of easy money - a run that started when then U.S. Federal Reserve Chairman Alan Greenspan turned on the monetary spigots in March 1995 - seem to have made investment bankers greedy.

And reckless.

Yes, they had risk management, but it mostly used the "Value at Risk" system invented by JPMorgan Chase & Co. (JPM) in the early 1990s. VAR appears to have been designed to let the traders get on with the business of making real money, while at the same time keeping the top brass from worrying too much about the risks traders were taking. It makes a number of mathematical assumptions that are provably false in real life, then assesses the "99% confidence limit" of the loss that may be incurred by each trading position at most 1% of the time (this is usually done by modeling the price behavior of a particular security as a Gaussian normal curve - a "bell curve," and then taking the point 2.36 standard deviations from the mean).

One big problem with this approach to managing risk is that it doesn’t tell you what can happen the other 1% of the time, when the VAR limit is exceeded. But the top managers of the investment banks were lulled into believing that other 1% didn’t matter: After all, they came to believe, if it was only a 1% probability, how dangerous could it be? However, since VAR was calculated from daily price movements, that 1% actually was quite important.

Even if VAR is modeling monthly movements, an exceptionally conservative use of it recommended by international regulators for the Basel II bank regulating accords, 100 months is still only 8.33 years. Looking at the possibility of going bankrupt every 8.33 years and viewing that as an acceptable risk is absolutely not something that bankers should be doing.

The other problem with VAR is that, in most cases, it depends on an assessment of the "volatility" of the security concerned - how much that security bounces around. However, volatility is by definition low in quiet markets and much higher in turbulent markets. Hence, the system’s assessment of risk is low when markets are quiet, allowing traders to pile on positions like madmen, and then zooms upward when things go wrong. At that point positions cannot be unwound.

As you can see, "a culture of risk management at every level" is not a great deal of use if you’re using dozy metrics like VAR to measure risk. The problem is made worse if you indulge in excessive leverage.

Traditionally, the maximum leverage for Wall Street broker-dealers was held to be 20 to 1. That level was always fudged a bit, partly by pretending that so-called "subordinated" debt was the equivalent of equity, which it obviously isn’t. So, while this 20-to-1 ratio is fine when your assets consist of commercial paper, bonds and shares that can be more-easily valued because they are more liquid and trade every day, it is far too high when the asset mix has come to include investment real estate, private equity stakes, hedge fund positions, credit default swaps and other derivatives positions that do not even appear on the balance sheet.

Scaling up from 20 to 1 to 30 to 1 - as Lehman did - is asking for trouble.

Even if the off-balance-sheet credit default swaps [CDS] and other derivatives don’t give you trouble, and there are no assets parked in "structured investment vehicles," or SIVs, that suddenly must be taken back onto the investment bank’s balance sheet. An institution that is levered 30 to 1 needs to see a decline of only 3.3% in the value of its assets before its capital is wiped out. In a global credit crisis such as the one we’re navigating right now, even if some of the assets are rock-solid Treasuries and such, a 3.3% decline can happen frighteningly quickly: You only need to see a 10% decline in value of a third of your assets.

If that seems reckless to you, consider this: Lehman’s leverage is not exceptional among Wall Street investment banks. According to the most recent quarterly financial statements (focusing on the balance sheet as of May or June), while Lehman’s leverage had been brought down to 23.3 times through asset sales, Morgan Stanley’s was still 30.0 times, Goldman Sachs’s 24.3 times, and Merrill Lynch’s was an astounding 44.1 times.

Far be it from me to contribute further to Wall Street’s current gloom. So do the research and come to your own conclusions.

Original post

Comments

[Alan von Al...:]

Thank you, sir. Very informative.

2008 Sep 12 07:03 AM

[billddrummer:]

Leverage kills. Thank you for this analysis.

2008 Sep 12 11:08 AM

[Roger Knights:]

People who liked this article should read <i>The Black Swan,</i> by Nassim Taleb. It is very critical of people who use Gaussian methods to ignore the 1% chance of catastrophe (the incalculable "black swan" event).

2008 Sep 12 11:17 AM

[JasonC:]

Um, but are the asset exposures all unhedged longs, never offsetting positions?

Bit of a problem using such a simplistic model of risk.

VAR can be made more conservative by modeling the asset process with fatter tails or allowing for a correlation copula that let's large zigs be more correlated with each other than small zags. There is nothing fundamentally wrong with it.

Yes high leverage if naked is dangerous, but investment banks do not typically simply own long their entire asset position, with no offsetting hedges.

Suppose a Lehman trader puts on a wide butterfly spread on a given stock. What is the asset level? The full premium for that butterfly, which may have an 85% chance of ending in the money. Ok, instead he holds a put on a stock in the trading desk's portfolio - what is the asset level? The full premium of the put plus the full value of the stock. What's the actual downside? Much less than that, unless the options clearing corporation is bankrupt.

Offsetting and hedged positions are why one needs to use a mathematical analysis of the portfolio's response to worst case price movements to estimate risk, and cannot simplistically divide the total asset line of the balance sheet by the tangible equity line.

2008 Sep 12 01:17 PM

[Duude:]

"Lehman's Risk Management Strategy May Have Caused the Problems"

Ya think? Actually, I wouldn't place the blame solely on VAR. One problem with all risk management theory is garbage in, garbage out. The fact that these investment bankers didn't have a clue that the risk adjusted pricing criteria used was total crap, made VAR useless. Compound that with heavy leverage and you have a disaster in the making. Clearly, VAR doesn't take into consideration excessive greed for year end bonuses are more than enough enticement for bankers to skip the dreary and time consuming duties of careful due diligence. However, there is an upside to this wall street story. It seems to me, that for every street firm that goes under, perhaps one survivor may read the tea leaves and spring for a new department in due diligence at least until the next big wall street profit surge.

2008 Sep 13 09:54 AM

[oldgoldbug:]

Thank you to author and commentators who are obviously very knowledgeable. The amount of information available at a mouse click is simply astounding.
Right now I'm a bit surprised we haven't seen more casualties in the hedgies from the massive crash in commodities. It would seem that they would be highly leveraged as well. Perhaps the liquidity in those markets helped them dodge the bullet.

2008 Sep 13 10:17 AM

[PeteyPete:]

Great article!

2008 Sep 14 02:02 AM

[PeteyPete:]

Great article!

2008 Sep 14 02:02 AM

[morph366:]

Absolutely right to stress the fundamental problem with all of risk management - it applies dubious concepts from the normal distribution to time series analysis. That's why financial engineers talk about 25 Standard Deviation events that should only happen once in a trillion years or whatever - right now they're happening all over Wall Street Apart from Taleb's book on this I have also written on the subject of bogus application of techniques from physics to finance - so called econonphysics in a book called Long/Short Market Dynamics (Wiley 2007).
Please excuse the shameless plug but as a result of the hubris of many so called "high powered" quants and the financial models that have come out of their sheds, most banks have balance sheets that hardly anyone (I am being kind) understands and with risks that cannot be quantified

2008 Sep 14 02:03 AM

[Ransome:]

Modeling is commonly used in the sciences for predictive purposes. There are two components, the model and the interpretation of the output. Similar output may be interpreted differently depending on the fortune teller. Most models should be tested robustly (validated) and interpretations confirmed. Einstein said there are too many components in an economy and it was not predictable.

The most successful models have very few variables, but having only a few variables is no guarantee of success if each variable is the result from an infinite number of variables that are not themselves predictable. Science relies on the Laws of Nature as a foundation. No such foundation exists in economic modeling.

2008 Sep 14 08:32 AM

[Eric Fu:]

Thanks for your thoughtful article! But I think we should be a little cautious to blame all the issue on VaR. I think there must be some management mistakes or careless. We could always see the moral hazard in using VaR. Usually, when we adjust VaR to 95% confidence interval which means some thing will be happened every 20 days, i.e. once a month, should be very usual. But we also know it is troublesome to explain to the CFO or Cs about the reason every time. VaR won't tell us how much we are going to expose, but at least it shows the possibility. While, the director of the risk will just simply ignore the VaR fact and change the confidence level to 99%, i.e. once a season. So now everyone is happy?

2008 Sep 15 08:17 PM