To explain the 2008 financial crisis a two pieces puzzle could suffice.

Sir, Tim Harford writes, “Raghuram Rajan, when he was chief economist of the IMF, came closest to predicting the 2008 financial crisis. He later observed that economists had written insightfully on all the key issues but had lacked someone capable of putting all the pieces together”, “How economics can raise its game” June 29.

According to 2004’s Basel II, a corporate rated AAA to AA, could offer banks to leverage their equity 62.5 times (100%/(8%*20%)) with its risk adjusted interest rate, while one rated BB+ to BB-, or not rated at all, could only offer banks to have their risk adjusted interest rate leveraged 12.5 times (100%/(8%*100%))

Sir, I am not arguing whether it is better to be a hard or a soft economist but, any economist looking at that proposition and not seeing it would cause serious misallocation of bank credit, should either go back to school, perhaps to take some classes on conditional probabilities, or go out on Main-street, and learn a bit of what real life is about.

62.5 times leverage? What banker could dare resists that temptation and stay out of competition thinking, what if that AAA to AA rating is true?

PS. That leverage applied for European banks and US investment banks supervised by SEC.

@PerKurowski