As of September 2002, Iowa had 435 insured banks, of which 363 were state-chartered; total insured bank assets amounted to $53 billion. The Division of Banking supervises and regulates the state's chartered banks, loan companies, and mortgage bankers/brokers. Throughout the 1990s and into the early 2000s, community banks in Iowa (those with under $1 billion in assets) saw a decline in net interest margins (NIMs) (the difference between the lower rates offered to savers and the higher rates charged on loans), due in part to increased loan and funding competition. To combat a decline in core deposits, Iowa community banks have increasingly relied upon large time deposits or borrowing (especially Federal Home Loan Bank advances) to support their assets.