Bank capital requirements, business cycle fluctuations and the basel accords: A synthesis

Abstract

In order to survey the mechanisms through which the introduction of Basel II bank capital requirements is likely to accentuate the procyclical tendencies of banking, this paper brings together the theoretical literature on the bank capital channel of propagation of exogenous shocks and the literature on the regulatory framework of capital requirements under the Basel Accords. We conclude that the theoretical models that revisit the bank capital channel under the new accord generally support the Basel II procyclicality hypothesis and that the magnitude of the procyclical effects essentially depends on (i) the composition of banks' asset portfolios, (ii) the approach adopted by banks to compute their minimum capital requirements, (iii) the nature of the rating system used by banks, (iv) the view adopted concerning how credit risk evolves through time, (v) the capital buffers over the regulatory minimum held by the banking institutions, (vi) the improvements in credit risk management and (vii) the supervisor and market intervention under Basel II. The recent events and instability in financial markets all over the world have led the procyclicality issue to enter the agendas of several political international fora and some measures to mitigate procyclicality are being put forward. The bank capital channel literature should now play an important role in evaluating their effectiveness. © 2009 Blackwell Publishing Ltd.