For: CDO

Collateralized debt obligations (CDOs) are a type of structured asset-backed security (ABS) whose value and payments are derived from a portfolio of fixed-income underlying assets. CDOs are assigned different risk classes, or tranches, whereby "senior" tranches are considered the safest securities. Interest and principal payments are made in order of seniority, so that junior tranches offer higher coupon payments (and interest rates) or lower prices to compensate for additional default risk.

A few academics, analysts and investors such as Warren Buffett and the IMF's former chief economist Raghuram Rajan warned that CDOs, other ABSs and other derivatives spread risk and uncertainty about the value of the underlying assets more widely, rather than reduce risk through diversification. With the advent of the 2007-2008 credit crunch, this view has gained substantial credibility. Credit rating agencies failed to adequately account for large risks (like a nationwide collapse of housing values) when rating CDOs and other ABSs.

Many CDOs are valued on a mark to market basis and thus have experienced substantial write-downs on the balance sheet as their market value has collapsed.

Market history and growth

The first CDO was issued in 1987 by bankers at now-defunct Drexel Burnham Lambert Inc. for Imperial Savings Association, a savings institution that later became insolvent and was taken over by the Resolution Trust Corporation on June 22, 1990. A decade later, CDOs emerged as the fastest growing sector of the asset-backed synthetic securities market. This growth may reflect the increasing appeal of CDOs for a growing number of asset managers and investors, which now include insurance companies, mutual fund companies, unit trusts, investment trusts, commercial banks, investment banks, pension fund managers, private banking organizations, other CDOs and structured investment vehicles.

CDOs offered returns that were sometimes 2-3 percentage points higher than corporate bonds with the same credit rating.

It may also reflect the greater profit margins that CDOs provide to their manufacturers.

A major factor in the growth of CDOs was the 2001 introduction by David X. Li of Gaussian copula models, which allowed for the rapid pricing of CDOs.

In late 2005 research firm Celent estimated the size of the global CDO market at USD 1.5 trillion and projected that the market would grow to nearly USD 2 trillion by the end of 2006.

Concept

CDOs vary in structure and underlying assets, but the basic principle is the same. A CDO is a type of Asset-backed security. To create a CDO, a corporate entity is constructed to hold assets as collateral and to sell packages of cash flows to investors. A CDO is constructed as follows:

• A special purpose entity (SPE) acquires a portfolio of underlying assets. Common underlying assets held include mortgage-backed securities, commercial real estate bonds and corporate loans.