Goldman Sachs’ VaR models and risk models started to show little cracks or discrepancies. They were small, but they shouldn’t have been there. Rather than ignore these discrepancies, Goldman Sachs tried to understand what was going on. When it couldn’t figure out what was going on they bailed out of mortgage-backed securities.
How then do we account for that story that made the rounds in the summer of 2007? It concerns Goldman Sachs, the one Wall Street firm that was not, at that time, taking a hit for billions of dollars of suddenly devalued mortgage-backed securities. Reporters wanted to understand how Goldman had somehow sidestepped the disaster that had befallen everyone else. What they discovered was that in December 2006, Goldman’s various indicators, including VaR and other risk models, began suggesting that something was wrong. Not hugely wrong, mind you, but wrong enough to warrant a closer look.
RISK Mismanagement – What Led to the Financial Meltdown – NYTimes.com