Small banks tend to make more profit over time when they provide loans to small businesses under $250,000. This is because small businesses rely heavily on banks for funding, and these loans help small banks increase their profitability. Large banks, on the other hand, are not significantly affected by lending to small businesses. The study used data from U.S. commercial banks in 1994 and 1995 to analyze the relationship between bank profits and small business lending, considering different levels of risk.