Leave aside the bickering whether yesterday's stress test results solve the long-term problems facing America's financial sector. Nineteen banks now know either that they have passed or failed. For those informed by the Treasury that they need to raise more capital, scouring the globe to find it is the challenge.

The two most important issues for investors relate to size and process. For starters, the aggregate amount of capital that needs to come from private sources is a moving feast. In addition to the shortfall calculated by the Treasury, the amount also depends on the proportion of troubled asset relief programme funds the healthier banks wish to repay, as well as the value of potential asset sales.

Assuming strong banks initially want to pay back half their Tarp capital, while weaker banks raise their tangible common equity to risk-weighted asset ratios to between 4 and 5 per cent, Goldman Sachs reckons about $130bn of additional capital is needed. Converting all private preferred shares into common stock raises about $45bn. Asset sales could net up to $30bn (executed and proposed sales already top $15bn).