1971    -999    -999     7.9     9.4     8.2     6.8    11.7     8.3     8.8     8.1     7.3     9.6
1972    12.3     9.1     9.8    10.8     7.1     8.8     9.4     7.2     9.3     6.4     7.4    12.2
1973     8.9     8.2     7.7     9.2     8.2    10.2     7.7     7.8     7.9     6.4     9.0     5.6
1974     6.3     6.8     8.3     8.2     6.8     8.1     6.4     9.4    10.0     6.2     7.9     6.8
1975     6.8     7.6     7.8     8.6     6.1     7.4     6.3    10.3     8.8     5.9     9.2     6.4
1976     8.8     7.7     8.9     9.7     9.4    11.3    12.2     7.7     6.7     7.4     6.6     8.2
1977     6.6     9.9     9.8    10.6     5.8     9.6     6.3     9.2    11.0     9.0     9.1     7.9
1978     9.4    10.4    10.7    12.1     8.1     6.7     8.5     9.7     8.7     8.7     9.3     6.8
1979     9.9     9.8     9.0     9.4     8.8     9.4     8.8     7.1    10.3     8.3    10.1     9.8
1980     6.7     7.6    12.6     9.4     7.9     7.8     5.9     8.5     9.4     7.5    10.8     6.7
1981     7.0    10.7     9.1     7.7     8.3     6.6     7.3     9.2    10.8    10.1     6.9     7.5
1982     5.8     6.1     7.7    10.6     9.0     7.5     7.1     7.8    10.7     7.9     7.6     7.1
1983    10.0    10.9    10.0     9.4     9.0     7.4     7.3     7.8     9.8     8.1     7.4     9.7
1984     6.6     9.2     7.2     8.4     5.6     6.7     6.5     7.6    10.1     7.8     7.0     8.0
1985     6.0     8.4     7.0     7.3     9.9     6.9     9.1     8.1     7.8     6.6     6.4     8.7
1986     7.8     6.3    11.7     9.9     8.4    12.2     8.5     8.6    10.3     7.3     5.9     5.8
1987     7.8     7.8    11.6    10.2    11.2     9.4    10.2    10.5     9.0     7.0     8.0     6.5
1988     8.4     8.3     9.9     9.3     9.6     7.5     8.3     9.1    -999     8.9     7.2     8.1
1989     6.6     6.1     9.6     9.1     7.4     7.2     9.5     7.9     9.1     8.5     6.6     7.9
1990     7.2     8.8     9.0     9.1    11.7     7.6     7.6     7.1     8.9     6.0     7.2     5.3
1991     7.3     6.8    -999    -999    -999    -999    -999    -999    -999    -999    -999    -999