Schwerdtfeger 18Z pressure 1985 - 986.6 984.4 984.6 986.6 981.8 972.3 982.8 972.9 974.4 970.6 979.2 1986 986.6 992.9 990.3 980.8 993.3 991.4 980.4 982.7 978.0 972.7 975.0 981.4 1987 992.8 988.3 986.5 988.1 983.4 988.3 992.7 975.5 989.3 979.3 978.3 985.1 1988 988.2 984.3 986.1 983.9 990.5 995.6 976.2 975.2 983.1 990.5 980.8 982.2 1989 984.5 985.7 984.4 988.1 971.3 980.9 979.2 984.5 982.7 974.0 975.9 988.7 1990 987.8 982.4 985.5 991.8 998.1 988.0 997.2 981.9 971.6 981.9 983.0 983.6 1991 981.9 988.4 981.8 985.4 987.7 989.6 992.4 982.6 981.0 977.7 983.5 994.5 1992 987.8 995.9 987.5 984.8 989.9 995.2 981.0 - - - - - 1993 - 976.9 984.3 978.9 981.0 975.5 - - - - 962.0 965.6 1994 967.5 965.5 961.5 966.8 967.9 980.4 969.9 - - - - - 1995 - - - - - - - - - - - - 1996 - 989.7 983.9 977.0 984.4 980.7 980.6 986.5 986.3 970.1 984.7 983.1 1997 985.6 986.4 976.3 981.5 969.6 984.0 975.7 973.6 977.5 973.6 984.9 986.8 1998 981.9 977.1 978.1 971.0 978.6 973.3 975.8 975.0 984.4 975.8 969.9 978.4 1999 979.2 984.2 981.0 977.6 974.9 995.7 975.5 979.3 978.2 960.7 967.6 970.9 2000 975.1 979.2 980.1 979.4 979.5 981.1 978.1 979.8 984.7 971.8 977.8 992.4 2001 987.9 984.5 980.9 975.3 981.1 979.0 983.1 979.0 974.3 969.2 972.5 973.5 2002 979.9 973.8 986.5 976.9 989.1 990.7 984.7 974.3 982.1 985.5 978.8 975.0 2003 987.2 986.4 981.5 974.0 974.7 988.2 975.8 973.1 976.7 969.4 979.4 989.6 2004 981.9 991.4 980.6 975.6 978.4 975.4 974.6 978.8 978.9 976.1 972.7 987.2 2005 983.3 975.9 979.2 975.0 976.7 985.8 977.2 973.6 973.0 967.4 976.0 991.3 2006 982.0 981.0 980.9 983.2 973.1 977.0 973.3 986.3 979.4 971.9 974.7 979.0 2007 982.3 978.9 985.5 980.1 981.9 982.0 992.8 975.3 973.7 - - - 2008 - 978.3 982.5 983.7 980.6 976.3 978.4 - 969.3 972.2 976.2 978.7 2009 978.9 984.4 980.5 982.6 987.8 989.4 987.8 986.3 978.9 975.1 981.2 980.7 2010 993.8 988.6 983.6 978.7 - 974.3 967.9 970.5 - 972.4 972.3 987.1 2011 989.1 983.4 988.2 985.8 975.8 984.9 982.4 984.3 - - - 974.1 2012 975.3 983.0 - - - - - - - - - - 2013 - 976.2 973.7 981.2 981.2 992.3 977.4 987.4 987.6 979.6 977.1 982.7 2014 986.6 981.5 979.8 977.0 980.9 979.2 981.3 971.1 980.2 969.8 982.4 980.1 2015 981.8 975.3 979.5 977.2 982.6 982.7 972.5 974.4 972.2 976.2 973.4 983.4 2016 976.3 979.2 976.5 982.9 979.5 975.4 984.8 986.0 969.9 976.9 988.6 985.8 2017 990.5 985.7 986.6 978.3 973.3 978.6 976.3 972.1 974.0 979.8 972.3 981.2 2018 981.2 979.9 982.0 983.2 981.4 984.4 981.2 986.3 971.7 970.1 973.3 979.3 2019 983.3 984.5 982.9 979.0 983.4 969.7 985.4 979.7 969.1 979.8 988.9 991.7 2020 988.2 979.5 977.5 978.7 975.7 976.0 981.5 982.2 981.7 969.6 974.3 973.5 2021 978.1 975.5 984.2 978.6 981.1 978.5 985.6 985.6 972.0 976.5 972.4 971.6 2022 980.1 977.6 978.3 979.1 975.6 988.5 972.9 974.7 971.2 977.2 973.0 973.1 2023 975.4 981.1 982.7 988.5 978.5 986.5 981.4 983.7 977.0 973.1 979.5 975.5 2024 979.1 981.8 979.4 973.2 974.0 973.0 986.3 989.5 982.3 - - -