YEAR JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC D-J-F M-A-M J-J-A S-O-N metANN 1966 25.2 23.8 23.1 17.6 13.6 10.9 10.6 10.6 11.6 15.6 21.8 22.8 24.0 18.1 10.7 16.3 17.27 1967 24.9 25.5 21.6 20.3 14.9 13.3 10.1 10.2 13.4 19.3 20.7 23.2 24.4 18.9 11.2 17.8 18.08 1968 25.8 24.0 20.3 16.0 12.1 11.8 10.2 9.0 11.9 15.8 19.5 22.5 24.3 16.1 10.3 15.7 16.63 1969 25.2 25.0 21.9 18.6 14.3 12.5 10.5 11.3 13.1 19.7 22.2 23.2 24.2 18.3 11.4 18.3 18.07 1970 25.1 25.9 23.8 16.7 13.9 11.8 10.9 11.1 12.8 17.2 20.3 24.9 24.7 18.1 11.3 16.8 17.73 1971 25.6 24.4 22.6 18.3 13.5 11.6 10.7 10.6 12.8 14.9 17.6 22.9 25.0 18.1 11.0 15.1 17.29 1972 26.2 27.4 23.7 999.9 17.3 12.4 10.4 10.9 13.3 17.4 22.3 27.2 25.5 20.5 11.2 17.7 18.74 1973 25.4 25.2 22.6 18.6 14.8 10.4 11.4 10.6 11.7 15.9 19.6 23.3 25.9 18.7 10.8 15.7 17.78 1974 26.5 24.1 23.9 16.9 13.6 11.3 10.9 11.5 13.8 15.4 19.5 24.3 24.6 18.1 11.2 16.2 17.56 1975 24.0 26.7 21.8 18.3 14.7 12.0 11.3 11.0 13.3 16.0 20.7 24.3 25.0 18.3 11.4 16.7 17.84 1976 25.1 26.8 24.3 19.4 15.6 11.9 11.9 12.0 14.5 17.5 18.8 24.9 25.4 19.8 11.9 16.9 18.51 1977 26.1 27.1 22.3 19.9 12.9 13.0 12.8 12.6 13.9 18.1 21.1 27.0 26.0 18.4 12.8 17.7 18.73 1978 26.5 999.9 24.9 21.8 14.4 11.5 10.6 11.7 999.9 17.2 21.3 23.3 27.0 20.4 11.3 17.5 19.03 1979 26.2 25.5 23.8 19.1 13.7 12.1 11.0 10.6 12.8 999.9 21.3 25.3 25.0 18.9 11.2 17.1 18.04 1980 27.3 24.9 25.1 17.0 15.5 11.9 11.2 12.1 15.5 15.2 22.2 23.9 25.8 19.2 11.7 17.6 18.60 1981 25.4 22.6 23.0 21.6 15.0 9.7 10.6 10.8 15.1 17.6 17.6 22.0 24.0 19.9 10.4 16.8 17.74 1982 24.3 25.7 21.3 19.2 14.0 11.1 10.0 13.4 13.6 17.8 999.9 25.1 24.0 18.2 11.5 17.4 17.77 1983 26.7 25.3 23.5 18.6 15.7 13.5 10.5 13.3 14.7 18.5 19.3 23.2 25.7 19.3 12.4 17.5 18.73 1984 25.3 24.9 20.6 19.3 14.2 11.5 10.3 9.9 12.7 17.2 19.9 22.2 24.5 18.0 10.6 16.6 17.42 1985 25.4 28.2 24.6 18.3 14.9 13.2 11.6 11.4 14.3 16.8 21.8 21.2 25.3 19.3 12.1 17.6 18.56 1986 26.7 23.5 23.2 18.1 14.2 12.3 9.2 9.4 13.5 14.4 20.7 22.9 23.8 18.5 10.3 16.2 17.20 1987 24.3 25.4 23.0 19.8 13.0 13.0 11.2 11.4 15.0 18.0 19.6 25.0 24.2 18.6 11.9 17.5 18.05 1988 25.0 26.0 23.7 20.3 15.0 13.6 10.7 11.5 13.8 17.3 19.4 22.8 25.3 19.7 11.9 16.8 18.44 1989 24.9 26.4 23.1 19.5 14.8 10.5 9.4 10.6 14.1 15.0 22.0 23.8 24.7 19.1 10.2 17.0 17.76 1990 24.4 24.0 23.3 18.2 15.0 10.1 9.9 11.0 14.0 16.3 20.9 23.8 24.1 18.8 10.3 17.1 17.57 1991 25.9 26.6 23.2 19.9 16.3 13.0 11.6 11.7 14.1 19.4 19.2 24.9 25.4 19.8 12.1 17.6 18.73 1992 26.2 24.5 23.0 19.3 13.7 12.8 11.8 10.9 11.7 16.9 999.9 999.9 25.2 18.7 11.8 16.0 17.93