Would it be costly to require banks to raise equity to 30 percent of total assets?

In their recently published book, 'The Banker's New Clothes', Anat Admati and Martin Hellwig make a strong case that in order to reduce the risk of insolvency in major financial institutions, shareholders should be required to fund their lending and other investments to a much greater extent.

The authors argue that government regulation to reduce the risk of insolvency of major financial firms is desirable because failure of such firms has adverse effects that are analogous to those that can arise from accidents in nuclear power plants. When I discussed that analogy in an earlier post, I accepted (somewhat reluctantly) that it is appropriate. As a result of the interconnectedness of financial markets, it would probably not be possible to avoid major economic disruption if large financial institutions were allowed to fail when they became insolvent. That makes it desirable to find the least cost way of regulating them to make it less likely that they will become insolvent. Governments are thus presented with problems that are similar to those involved in regulating the nuclear power industry to reduce the risk that serious nuclear accidents will occur.

Admati and Hellwig suggest that the best way to reduce the risk of insolvency of major financial institutions is to require them to raise shareholder equity from current levels (which under Basel III can apparently still be as low as 3 percent of total assets) to 20-30 percent of total assets. The higher ratio of shareholder equity to total bank assets would provide greater scope for any future fall in the value of bank assets to be accommodated without insolvency.

The authors suggest that requiring banks to rely more on equity funding would impose little, if any, cost to society. In this post I want to focus specifically on the reasons they give for that view. I encourage readers who are interested in a broader discussion of this important book to read John Cochrane's review.

The authors argue that requiring banks to rely more on equity funding would impose little cost on society because it would offset the bias in favour of borrowing provided by government guarantees and tax systems. Banks and their creditors benefit from explicit guarantees to protect depositors as well as implicit guarantees associated with the 'too big to fail' concept. These guarantees enable banks to borrow on more favourable terms than would otherwise be possible. Tax systems tend to favour borrowing because they make interest paid a tax deductible expense.  (The dividend imputation system in Australia reduces this bias to some extent but, as acknowledged by the Henry Tax Review, there is still a bias in favour of foreign borrowing and Australian banks rely heavily on this source of funds.)

The authors point out that equity ratios of banks were generally much higher in the 19^th century, prior to the existence of government guarantees.  In the US, until the middle of the 19^th century, equity levels around 40-50 percent of banks' total assets were typical and early in the 20^th century it was still common for banks to have equity of around 25 percent. The picture seems to have been broadly similar in Australia. Data presented in an article by Charles Hickson and John Turner shows (apparently) that the average equity to deposit ratio of Australian banks declined from around 60 percent in the 1860s to around 20 percent in 1892. The subsequent depression would presumably have substantially depleted the equity of those banks that managed to remain in business. Adam Creighton, a journalist, implies that the surviving banks re-built their capital ratios following the depression, so that a century ago they maintained capital ratios of between 15 per cent and 20 per cent. (See: 'Time to Force the Big Banks to Hold More Capital', 'The Australian', 23 November, 2012.)

Admati and Hellwig point out that the proposed increase in bank equity would not interfere with core banking functions of accepting deposits and making loans. Given the current structure of balance sheets, the increase in equity levels would tend to displace additional borrowing from sources such as money market funds rather than bank deposits.

The authors point out that bankers' claims that equity is more costly than debt are flawed because they don't take account of the effect of increased equity in reducing the risk of bank failure and thus reducing the rate of return required by shareholders. Equity only seems costly because government guarantees provide an implicit subsidy on debt. The increase in equity could be accomplished without significantly disadvantaging existing shareholders by requiring banks to retain earnings rather than pay dividends, until equity levels have reached the minimum level.  

I am normally sceptical of claims that governments can improve matters when they attempt to offset the adverse effects of previous interventions by adding a further layer of regulation. It seems, however, that Anat Admati and Martin Hellwig have found an instance where the theory of second best provides a valid guide to policy action. There are strong grounds to argue that if governments cannot credibly bring the 'too big to fail' policy to an end, they should take decisive action to offset the effects that policy has had in encouraging banks to become more fragile.  In my view the authors' proposals deserve strong support.