1980 02 99.99 -99.99  26.10 
1980 03 99.99 -99.99  26.70 
1980 04 99.99 -99.99  26.80 
1980 05 99.99 -99.99  26.40 
1980 06 99.99 -99.99  26.30 
1980 07 99.99 -99.99  25.90 
1980 08 99.99 -99.99  25.90 
1980 09 99.99 -99.99  25.60 
1980 10 99.99 -99.99  25.70 
1980 12 99.99 -99.99  26.00 
1981 01 99.99 -99.99  25.50 
1981 02 99.99 -99.99  26.10 
1981 03 99.99 -99.99  26.70 
1981 04 99.99 -99.99  22.20 
1981 05 99.99 -99.99  26.10 
1981 06 99.99 -99.99  25.60 
1981 07 99.99 -99.99  25.50 
1981 08 99.99 -99.99  25.00 
1981 09 99.99 -99.99  25.60 
1981 10 99.99 -99.99  25.30 
1981 11 99.99 -99.99  25.40 
1981 12 99.99 -99.99  25.60 
1982 01 99.99 -99.99  26.30 
1982 02 99.99 -99.99  26.60 
1982 03 99.99 -99.99  26.40 
1982 04 99.99 -99.99  26.50 
1982 05 99.99 -99.99  26.10 
1982 06 99.99 -99.99  26.40 
1982 08 99.99 -99.99  26.50 
1982 09 99.99 -99.99  25.70 
1982 10 99.99 -99.99  26.00 
1982 11 99.99 -99.99  26.60 
1982 12 99.99 -99.99  26.60 
1983 01 99.99 -99.99  26.60 
1983 02 99.99 -99.99  27.60 
1983 03 99.99 -99.99  26.50 
1983 04 99.99 -99.99  27.40 
1983 05 99.99 -99.99  27.70 
1983 06 99.99 -99.99  27.20 
1983 07 99.99 -99.99  27.30 
1983 08 99.99 -99.99  26.70 
1983 09 99.99 -99.99  26.00 
1983 10 99.99 -99.99  25.60 
1983 11 99.99 -99.99  25.90 
1983 12 99.99 -99.99  25.80 
1984 02 99.99 -99.99  26.00 
1984 03 99.99 -99.99  26.20 
1984 06 99.99 -99.99  24.80 
1984 09 99.99 -99.99  25.30 
1985 05 99.99 -99.99  26.00 
1985 07 99.99 -99.99  25.30 
1985 08 99.99 -99.99  25.40 
1985 09 99.99 -99.99  25.40 
1987 10 99.99 -99.99  26.00 
1987 11 99.99 -99.99  26.40 
1987 12 99.99 -99.99  26.50 
1988 01 99.99 -99.99  26.40 
1988 02 99.99 -99.99  26.60 
1988 03 99.99 -99.99  26.60 
1988 04 99.99 -99.99  26.20 
1988 05 99.99 -99.99  26.20 
1988 06 99.99 -99.99  25.40 
1988 09 99.99 -99.99  25.60 
1988 10 99.99 -99.99  25.40 
1988 11 99.99 -99.99  25.40 
1988 12 99.99 -99.99  25.20 
1989 01 99.99 -99.99  26.00 
1989 02 99.99 -99.99  26.00 
1989 03 99.99 -99.99  26.20 
1989 04 99.99 -99.99  26.20 
1989 06 99.99 -99.99  26.00 
1989 07 99.99 -99.99  27.00 
1989 08 99.99 -99.99  25.70 
1989 10 99.99 -99.99  25.80 
1989 11 99.99 -99.99  25.80 
1989 12 99.99 -99.99  25.60 
1990 01 99.99 -99.99  26.20 
1990 02 99.99 -99.99  26.40 
1990 03 99.99 -99.99  26.40 
1990 04 99.99 -99.99  26.40 
1990 05 99.99 -99.99  26.50 
1990 06 99.99 -99.99  26.40 
1990 07 99.99 -99.99  26.00 
1990 09 99.99 -99.99  26.00 
