(33)The financial crisis has revealed a need for a better analysis of and response to macro-prudential problems, which lie at the interface between macroeconomic policy and financial system regulation. This will include a need to examine: measures that mitigate the ups and downs of the business cycle, including the need for credit institutions to build counter-cyclical buffers in good times that can be used during a downturn, which may include the possibility of building up additional reserves, ‘dynamic provisioning’ and the possibility to reduce capital buffers during difficult times, thus ensuring adequate availability of capital over the cycle; the rationale underlying the calculation of capital requirements in Directive 2006/48/EC; supplementary measures to risk-based requirements for credit institutions to help constrain the build-up of leverage in the banking system.