Most frequently occuring interest rate for new business within the reporting period (the two middle weeks of a given month). The average rates are calculated as unweighted arithmetic means from the interest rates reported to be within the spread. The spread is ascertained by eliminating the reports in the top 5% and the bottom 5% of the interest rate range. Since January 1991 the rates of banks in the new Länder have been included in the interest rate survey. Up to May 1986, deposits of less than DM 1 million with maturities of three months; from June 1986 up to October 1996, deposits of DM 100,000 and more but less than DM 1 million with maturities of one month to three months; from November 1996 up to December 2001, deposits of DM 100,000 and more but less than DM 1 million with maturities of 1 month.