He begins by considering the costs of the financial crisis that might be attributed to banks. Direct fiscal costs are likely to underestimate the impact on the wider economy of the financial crisis whereas the value of lost output, some of which might be permanent, might significantly overstate the costs attributable to banks. If authorities want to levy a tax on banks to reflect the costs of the crisis, then ". a more precise measure may be needed of banks' distinctive contribution to systemic risk", Andrew Haldane says. He attempts to provide one such measure based on ratings and bond yields to estimate the reduction in banks' funding costs that arises from perceived government support to safeguard stability. The estimates are no more than illustrative but suggest the costs are both large and largely accounted for by institutions that are perceived as 'too-big-to-fail'.