But this line of research needs to be pursued much further, incorporating the pre-crisis years, looking at various types of financial markets, and better motivating our analysis in terms of theory.
Establishing an “optimal” threshold above which the size of the financial sector is harmful and below which it is beneficial for society is much more complicated than identifying multiples  8  Keyes, B., Mukherjee, T., Seru, A., and V. Vig, 2010. Did securitization lead to lax screening? Evidence from subprime loans. Quarterly Journal of Economics 125, 307–362.