How to pick the bank stocks for investment ?

(1) CASA ratio
CASA ratio stands for current account to saving account ratio. The CASA ratio tells the contribution of current and savings accounts to the bank's liabilities.since the bank has to pay the lowest interest on current and saving accounts ,the higher the CASA ratio the better the bank are.
For example, if a bank has rs.10 crores, then CASA PERCENTAGE tells how much of that money the bank has received from the current account and from the savings account customers