The more relevant margin is that between the average interest rate on bank loans and the average cost of the funds used by banks to finance their loans. This is usually referred to as banks’ net interest margin. Between 2000 and 2007, the net interest margin on the major banks’ Australian operations had narrowed by about 100 basis points (Graph 5).
Seminar, Bd. 8., Stuttgart 1979 Statutes of the ESCB and the ECB, available at http://www.ecb.int/ecb/legal/pdf/en_statute_from_c_11520080509en02010328.pdf  BIS central bankers’ speeches  5