D_10 pressure 1980 - 957.1 952.6 957.6 954.2 - 966.9 953.2 952.1 944.2 957.9 955.5 1981 - 951.8 - 957.4 - - - - - - - - 1982 - - 945.5 946.1 953.8 956.7 963.3 943.1 940.0 - - - 1983 959.7 955.5 949.9 951.8 956.3 958.2 947.9 - 949.7 941.6 949.4 - 1984 - 954.8 952.0 952.7 960.7 - 953.6 959.9 946.0 945.4 950.0 964.4 1985 - 951.8 955.0 - - 957.5 - 953.3 - 946.9 - - 1986 956.0 966.1 954.0 - 956.9 950.4 950.5 954.5 - - - 952.5 1987 960.8 952.0 949.5 953.9 948.1 959.4 957.3 939.1 948.8 - - 954.7 1988 956.2 950.5 950.4 951.5 957.7 960.9 945.8 950.1 952.2 956.5 950.7 948.6 1989 956.3 951.1 948.5 954.0 943.0 949.2 951.9 957.2 952.9 950.1 946.3 957.5 1990 955.5 948.8 951.5 961.3 958.4 956.9 956.5 953.6 941.4 - - - 1991 - - - - - - - - - - - - 1992 - 959.1 952.0 951.1 954.6 961.2 949.1 953.1 943.5 949.1 948.6 952.3 1993 958.9 952.7 - - - - - - - 942.4 945.5 950.9 1994 952.2 951.4 948.5 950.8 954.3 - - - 956.4 949.0 951.9 948.7 1995 951.5 950.6 951.2 948.1 945.9 - - - - - - - 1996 - - - - - - - - - - - - 1997 - - - - - - - - - - - - 1998 - - - - - - - - - - - - 1999 952.8 952.2 952.9 942.2 945.8 - - - 950.9 942.3 946.3 944.9 2000 948.4 951.4 951.5 951.1 943.7 953.9 - - - - - 959.8 2001 954.4 953.4 - 950.7 959.9 950.2 - - - 945.1 - - 2002 957.0 - - - 961.1 957.0 - - 948.1 956.4 - - 2003 - - - - - - - - - - - - 2004 - - - - - - - - - - - - 2005 - - - - - - - - - - - - 2006 - - - - - - - - - - - - 2007 - - - - - - - - - - - - 2008 - - - - - - - - - - - - 2009 - - - - - - - - - - - -