Bank regulation, capital and credit supply: Measuring the Impact of Prudential Standards

The existence of a “bank capital channel”, where shocks to a bank’s capital affect the level and composition of its assets, implies that changes in bank capital regulation have implications for macroeconomic outcomes, since profit-maximising banks may respond by altering credit supply or making other changes to their asset mix. The existence of such a channel requires (i) that banks do not have excess capital with which to insulate credit supply from regulatory changes, (ii) raising capital is costly for banks, and (iii) firms and consumers in the economy are to some extent dependent on banks for credit. This study investigates evidence on the existence of a bank capital channel in the UK lending market. We estimate a long-run internal target risk-weighted capital ratio for each bank in the UK which is found to be a function of the capital requirements set for individual banks by the FSA and the Bank of England as the previous supervisor (Although within the FSA’s regulatory capital framework the FSA’s view of the capital that an individual bank should hold is given to the firm through individual capital guidance, for reasons of simplicity/consistency this paper refers throughout to “capital requirements”). We further find that in the period 1996-2007, banks with surpluses (deficits) of capital relative to this target tend to have higher (lower) growth in credit and other on- and off-balance sheet asset measures, and lower (higher) growth in regulatory capital and tier 1 capital. These findings have important implications for the assessment of changes to the design and calibration of capital requirements, since while tighter standards may produce significant benefits such as greater financial stability and a lower probability of crisis events, our results suggest that they may also have costs in terms of reduced loan supply. We find that a single percentage point increase in 2002 would have reduced lending by 1.2% and total risk weighted assets by 2.4% after four years. We also simulate the impact of a countercyclical capital requirement imposing three one-point rises in capital requirements in 1997, 2001 and 2003. By the end of 2007, these might have reduced the stock of lending by 5.2% and total risk-weighted assets by 10.2%.