An important trend among US commercial banks in past decades is their embrace of diversification. In the geographical dimension, banks are now lending across more states than they used to. While in 1997 the average bank conducted small business and mortgage lending across eight states, by 2017 this number rose to 15.
Banks are also expanding across business lines. Before it was dismantled, the Glass-Steagall Act largely forbade the integration of commercial banking, securities underwriting, and insurance. Now, more than 20% of US bank holding companies have security broker-dealer subsidiaries and half own at least one domestic insurance subsidiary.
