Whitlock 18Z pressure 1982 - 956.4 946.0 948.3 954.5 947.5 956.8 - 942.9 948.0 953.0 963.9 1983 962.9 963.4 953.4 948.6 952.7 955.6 947.7 945.6 949.3 936.9 942.8 955.1 1984 965.0 957.4 948.3 948.7 955.9 947.2 943.2 951.8 948.1 940.8 948.0 963.2 1985 961.5 955.5 953.6 953.4 954.0 950.1 939.3 952.3 940.8 942.2 940.4 949.9 1986 957.8 963.7 959.3 949.5 958.1 958.3 948.4 951.1 945.4 941.5 944.1 952.0 1987 964.6 957.9 954.9 957.1 950.9 955.3 959.9 941.9 956.5 947.1 947.4 956.6 1988 960.0 954.3 953.6 952.9 958.4 962.0 945.8 943.2 952.3 958.7 949.9 952.8 1989 955.3 953.6 952.8 955.7 940.4 949.1 947.4 952.6 950.9 943.6 945.0 959.3 1990 958.9 950.8 954.2 960.8 965.6 955.6 964.5 949.1 940.0 949.9 952.5 954.7 1991 953.0 958.4 950.2 954.8 955.7 958.0 959.3 950.4 949.4 945.6 - 963.3 1992 - - - - - - - - - - - - 1993 - - - - - - - - - - - - 1994 - - - - - - - - - - - - 1995 954.1 954.5 963.6 956.1 952.9 962.0 973.3 959.4 950.4 953.0 952.0 952.0 1996 960.0 963.5 957.4 952.8 959.0 954.8 956.4 - - 945.7 960.7 959.4 1997 962.4 961.1 952.7 959.2 946.8 959.3 - - - - 960.6 964.0 1998 959.1 954.2 955.6 - - - - - - - - - 1999 - - - - - - - - - - - - 2000 - - - - - - - - - - - - 2001 - - 956.7 950.6 956.7 953.3 958.9 953.6 950.8 944.2 948.8 949.7 2002 956.0 950.3 962.1 952.2 963.3 964.6 960.1 949.7 957.7 961.1 955.2 951.4 2003 963.1 962.7 - - - - - - - - - 965.5 2004 957.7 966.3 955.5 951.8 953.3 950.4 948.8 954.2 954.4 951.4 949.7 963.5 2005 - - - - - - - - - - - - 2006 - - - - - - - - - - - - 2007 - - - - - - - - - - - - 2008 - - - - - - - - - - - - 2009 - - - - - - - - - - - - 2010 - - - - - - - - - - - - 2011 - 955.7 960.5 959.4 949.6 957.6 955.0 958.5 959.6 949.9 958.1 949.3 2012 949.9 956.5 954.6 953.1 949.7 961.8 950.2 952.7 950.2 950.1 960.0 961.1 2013 958.6 950.1 948.2 953.7 954.6 964.9 950.5 961.7 961.0 953.7 951.3 957.3 2014 960.6 954.5 952.9 951.8 954.3 953.3 954.2 943.8 954.9 942.9 956.4 954.5 2015 956.6 949.3 953.9 951.2 956.1 955.8 946.6 947.4 946.4 949.2 947.9 957.8 2016 950.8 953.2 949.9 955.3 954.6 948.7 958.8 959.1 943.5 950.3 963.2 960.2 2017 964.1 959.6 958.1 953.5 947.9 953.0 949.7 945.1 948.7 952.1 947.4 955.8 2018 955.6 953.5 954.9 958.7 955.5 957.2 954.4 960.2 944.0 944.3 948.4 953.2 2019 957.1 958.5 955.4 953.1 957.2 942.6 959.1 952.0 943.9 953.8 963.0 965.7 2020 962.1 953.9 949.2 953.1 950.7 950.0 953.2 953.9 954.8 944.2 948.6 948.6 2021 953.0 949.7 955.8 951.6 953.8 953.6 958.9 959.0 945.2 951.3 947.4 946.4 2022 954.2 951.7 952.7 953.0 949.4 960.8 947.7 948.4 945.5 951.1 947.2 949.2 2023 950.8 955.7 957.1 962.6 952.6 961.0 954.5 957.0 950.5 947.4 953.5 950.0 2024 953.2 954.9 952.5 946.6 947.8 947.7 960.2 962.9 955.6 - - -