In a Yahoo! Finance article written on October 17, 2008, Stein explained that his understanding of debt obligations based on real estate loans was less than the "staggeringly large" amount of obligations that were created through trading in derivatives of those, and so why it wasn't as similar to collapse of junk bond empire in early 1990s as he thought it would be: "Where I missed the boat was not realizing how large were the CDS default swaps based on the junk mortgage bonds."