Ken Lewis is not a happy camper. Or, as the Bank of America boss put it himself even better: "I've had all the fun I can stand in investment banking at the moment." On leveraged loans, BofA actually managed to avoid the worst excesses of the buy-out boom. The bank's pain came more in trading credit and structured products, such as mortgage-backed securities where, at the risk of simplifying, the hedging did not work out as planned.

Overall, it is not looking pretty for Wall Street. Who knows what the return profile will look like for collateralised debt obligations, given how little data there is on underwriting revenues. With regards to leveraged loans, the comparisons are a little easier, albeit on a back-of-the-envelope basis. From 2004 to 2007, JPMorgan, Goldman Sachs, Citigroup, Lehman Brothers and BofA, earned aggregate revenues of about $14bn from financial sponsors, according to Dealogic. The write-downs announced in the past quarter alone amount to between $5bn and $5.5bn. Lop those off the revenues, adjust for taxes and compensation and you end up with what looks like a pretty underwhelming return.