1969    -999    -999    -999    -999   -54.7   -57.8   -58.3   -58.5   -57.7   -55.7   -53.2   -50.6
1970   -49.1   -48.9   -52.7   -53.3   -54.5   -56.6   -58.1   -58.1   -56.1   -53.7   -51.0   -52.9
1971   -50.6   -51.4   -50.0   -50.7   -54.5   -55.2   -58.2   -57.8   -57.2   -55.3   -54.5   -52.6
1972   -51.3   -50.8   -51.0   -53.7   -54.1   -56.5   -57.2   -56.7   -56.4   -53.6   -50.3   -48.8
1973   -50.6   -47.7   -49.0   -52.0   -54.7   -57.8   -55.0   -57.4   -58.5   -54.2   -51.6   -49.5
1974   -49.9   -46.6   -50.7   -52.7   -53.9   -56.1   -57.8   -60.3   -56.6   -54.2   -53.3   -49.1
1975   -48.3   -48.2   -49.0   -51.3   -53.7   -54.9   -57.7   -58.4   -57.7   -52.3   -51.7   -51.0
1976   -52.3   -46.6   -50.5   -51.5   -54.4   -58.6   -59.6   -58.5   -57.5   -54.4   -54.0   -52.0
1977   -49.2   -49.6   -51.2   -54.9   -55.5   -57.5   -59.1   -59.4   -59.4   -56.3   -53.2   -50.8
1978   -49.3   -48.1   -48.7   -50.1   -53.0   -57.8   -59.8   -58.9   -56.7   -56.4   -52.9   -52.5
1979   -48.9   -49.1   -49.0   -50.8   -54.7   -58.6   -58.3   -60.2   -58.9   -56.7   -55.3   -51.1
1980   -52.3   -49.8   -51.6   -53.3   -54.2    -999   -57.9   -58.8   -59.1   -56.0   -55.5   -50.4
1981   -48.7   -48.8   -49.5   -52.7   -55.3   -57.3   -57.9   -59.6   -57.7   -57.2   -55.1   -50.8
1982   -49.4   -49.8   -50.0   -51.1   -53.1   -56.5   -58.8   -59.2   -57.8   -56.7   -53.5   -52.6
1983   -51.2   -49.5   -49.0   -51.3   -54.3   -58.0   -58.0   -57.5   -58.9   -57.0   -51.8   -50.5
1984   -48.9   -51.1   -51.1   -52.7   -54.6   -57.0   -57.7   -57.8   -57.4   -56.4   -52.1   -48.6
1985   -49.6   -49.2   -50.9   -52.9   -55.8   -55.7   -56.3   -58.4   -57.8   -54.6   -51.5   -49.2
1986   -49.6   -49.2   -51.0   -54.1   -56.8   -60.0   -57.8   -57.7   -56.4   -54.8   -53.2   -49.0
1987   -50.4   -49.4   -48.4   -52.5   -53.9   -57.6   -58.3   -57.4   -58.6   -55.6   -53.1   -48.9
1988   -50.6   -48.2   -49.4   -51.9   -52.9   -57.3   -56.3   -57.7   -56.4   -55.4   -51.0   -49.4
1989   -49.4   -49.0   -50.3   -53.3   -53.5   -54.9   -56.2   -56.7   -58.6   -56.3   -49.8   -52.7
1990   -51.0   -46.2   -49.2   -53.0   -55.1   -57.5   -57.3   -58.0   -57.1   -57.0   -54.8   -53.2
1991   -46.2   -45.2   -49.6   -53.0   -54.8   -58.8   -56.9   -57.7   -55.6   -55.8   -51.0   -52.0
1992   -47.4   -48.1   -49.8   -52.0   -55.3   -57.3   -50.2   -53.2   -51.3   -52.9   -44.5   -43.8
1993   -51.2   -48.9   -48.8   -52.9   -53.7   -54.3   -56.7   -57.2   -56.3   -55.4   -53.7   -50.9
1994   -48.2   -48.4   -49.1   -53.3   -57.0   -56.9   -58.0   -58.8   -59.5   -58.4   -53.9   -47.6
1995   -47.5   -48.2   -49.6   -51.9   -47.2   -50.9   -56.0   -51.5   -51.0   -45.6   -47.3   -43.3
1996   -47.2   -48.4   -50.7   -53.1   -53.2   -55.4   -53.2   -55.2   -53.7   -53.4   -54.3    -999
1997    -999    -999    -999    -999    -999    -999    -999    -999    -999    -999   -53.8   -52.3
1998   -48.1   -45.5   -49.1   -49.1   -52.9   -54.5   -59.2   -59.9   -57.7   -57.1   -51.9   -51.0
1999   -48.0    -999    -999    -999    -999    -999    -999    -999    -999    -999    -999    -999