Banks use statistics for a great number of the services they offer. A bank works on the idea that someone will deposit their money and not withdraw all of it later on. They earn their profit by lending money to others with interest, and the money they use is the money other people deposit.
Bankers use statistical approaches to estimate the number of people who will be making deposits compared to the number of people requesting loans. A great example of statistics used in banking is the FDIC’s own quarterly publication called Statistics on Banking.