We design a new, implementable capital requirement for large financial institutions (LFIs) that are too big to fail. Our mechanism mimics the operation of margin accounts. To ensure that LFIs do not default on either their deposits or their derivative contracts, we require that they maintain an...

What are the quantitative effects of countercyclical capital buffers (CCyB)? I study this question in the context of a nonlinear DSGE model with a financial sector that is subject to occasional panics. A calibrated version of the model is combined with US data to estimate sequences of structural...