If transparency is the currency of trust, then investment banks are badly in the red. One of the most remarkable aspects of the latest round of quarterly reporting by the investment banks is the woeful lack of transparency and highly variable disclosure across the industry.

Take fixed income, the traditional engine room of the industry whose fortunes from one quarter to the next pretty much dictate the profitability or otherwise of an investment bank. The numbers are big, very big. In the first half of this year, JP Morgan generated $8.8bn in underlying revenues from fixed income, currencies and commodities. That's more than 40% of the total revenues in the corporate and investment bank, and nearly one fifth of group revenues at JP Morgan Chase.