- Bank Size The size of a bank was considered to be a key determinant on its performance or profitability. The economies of scale could enable the big size of banks to decrease the processing costs and other information gathering costs (Boyd and Runkle, 1993).Alkhatib (2012) used logarithm of total assets to indicate the bank size for the Palestinian commercial banks, and he found there was a statistically significant impact of bank size on bank performance.