$15.8 Billion current market capitalization. I wonder what their assets under management is? If it's higher, that would seem to say that the market values them less than the work they do.
It's a little different. They have trillions of asserts backed up mostly by debt and a small dose of equity. This is how most banks operated, and why they are so volatile. (Lehman was 30 to 1 debt to equity. Most banks are somewhere between 10 and 30 to 1)