1956 -999.0 10.6 10.5 14.8 14.9 13.8 14.7 12.9 14.6 10.1 11.7 8.3 1957 9.2 10.0 13.2 16.2 15.3 14.9 16.6 18.3 14.6 12.4 8.4 7.1 1958 7.7 9.8 11.2 13.5 15.1 13.9 14.4 14.2 12.8 11.2 10.2 10.3 1959 7.2 8.7 12.1 10.8 13.9 15.3 12.1 12.3 13.1 10.4 10.1 8.0 1960 7.5 -999.0 -999.0 -999.0 -999.0 -999.0 -999.0 -999.0 11.5 10.3 9.2 8.5 1961 7.0 11.2 14.1 15.7 16.6 14.7 17.5 17.1 16.2 11.7 12.3 9.7 1962 9.4 10.1 11.7 14.6 16.7 14.9 13.6 14.7 12.0 12.7 9.7 11.0 1963 8.5 8.5 10.2 12.6 13.4 14.9 11.9 14.5 13.8 11.3 10.5 9.0 1964 6.6 10.2 10.9 12.0 13.0 14.0 11.2 13.4 9.3 9.4 12.5 9.8 1965 7.5 9.5 9.2 11.8 14.4 11.5 12.8 14.9 11.1 11.4 9.8 9.9 1966 7.5 9.2 11.5 11.0 13.1 12.1 14.8 11.8 14.0 9.4 9.3 8.2 1967 9.4 9.7 11.5 13.3 14.7 13.3 12.2 11.9 10.6 12.5 10.2 8.1 1968 5.1 10.7 12.4 12.3 11.7 11.6 11.4 11.0 11.4 11.0 8.8 9.4 1969 6.8 8.7 10.2 13.6 12.9 14.4 11.3 12.3 11.8 10.3 9.4 9.7 1970 8.6 9.2 12.9 11.6 14.8 12.4 11.8 11.5 13.0 8.8 11.1 10.7 1971 8.4 10.6 12.4 11.9 11.8 11.5 13.6 15.1 11.7 12.5 10.1 9.3 1972 9.8 8.8 11.1 13.5 11.5 13.6 13.6 15.3 11.5 9.0 8.6 5.9 1973 7.7 9.9 9.8 13.1 14.2 13.5 10.4 13.5 14.4 11.7 11.0 8.6 1974 6.7 10.5 13.3 13.7 12.7 16.4 14.1 14.7 11.6 11.5 10.1 7.9 1975 9.8 8.0 10.3 13.4 15.1 14.5 12.4 11.9 11.3 10.6 12.1 9.8 1976 9.5 9.3 10.6 12.3 11.6 13.3 13.4 11.5 13.0 12.7 11.8 9.3 1977 8.8 9.2 10.0 12.0 12.8 14.4 14.7 14.0 10.8 11.4 8.5 8.2 1978 7.5 6.8 10.9 11.6 14.5 12.5 13.5 12.3 13.8 7.3 8.8 8.4 1979 6.1 9.4 11.0 13.6 11.1 13.4 12.5 11.8 13.4 9.3 9.6 8.0 1980 6.1 7.3 10.9 12.1 11.0 11.2 12.5 11.8 12.2 9.8 11.5 7.0 1981 7.6 8.1 11.1 9.9 11.2 10.1 12.9 12.9 10.4 7.9 9.9 6.2 1982 7.8 8.7 9.8 11.3 12.6 10.4 15.4 10.0 10.6 11.8 8.6 8.7 1983 8.2 9.1 12.8 13.9 13.5 14.5 12.7 14.0 12.2 11.1 9.1 8.6 1984 10.1 9.8 10.0 14.4 13.3 12.8 13.4 13.2 13.7 9.6 10.9 8.6 1985 8.4 8.8 13.2 14.7 13.1 14.2 10.8 14.2 13.4 11.9 8.5 8.4 1986 8.0 11.7 11.1 13.9 13.8 13.8 12.3 13.0 13.6 13.3 9.0 7.7 1987 8.5 9.5 11.7 13.0 12.7 14.4 14.7 13.1 12.7 10.1 11.1 8.5 1988 9.3 10.0 14.0 12.4 15.3 14.5 12.9 15.8 12.0 12.1 9.8 7.2 1989 8.9 10.8 10.9 10.9 13.2 14.6 13.6 14.9 14.8 14.1 8.1 11.5 1990 9.5 8.2 11.8 15.6 13.3 13.6 14.0 13.4 12.6 10.9 9.6 8.6 1991 7.6 9.2 11.6 13.7 14.9 14.1 14.7 12.3 12.4 10.7 11.4 8.6 1992 7.4 10.4 10.8 13.1 14.0 12.6 9.9 10.2 12.4 10.9 10.4 6.8 1993 8.2 9.2 12.3 11.6 12.8 15.2 11.2 11.3 9.5 11.3 9.3 7.1 1994 8.1 10.5 12.4 12.3 10.9 14.8 13.2 11.8 13.6 11.9 9.9 8.4 1995 7.6 8.7 11.7 13.2 12.6 13.9 14.2 11.4 10.8 9.9 11.2 9.7 1996 9.2 9.1 11.1 11.6 11.6 13.5 11.6 13.7 11.5 10.0 9.9 8.6 1997 6.7 9.8 14.4 13.4 11.4 13.2 13.0 13.1 12.9 10.3 9.2 8.2 1998 8.4 9.3 12.3 11.2 13.5 13.5 10.3 12.7 11.8 9.0 11.9 9.1 1999 7.6 8.5 11.7 12.3 11.6 14.6 12.7 12.3 12.2 10.3 8.7 9.2 2000 8.7 10.3 11.5 14.9 13.7 12.9 13.4 13.7 10.5 9.6 11.9 8.1 2001 7.1 8.0 11.4 13.0 13.4 13.2 12.9 13.0 11.4 11.9 10.3 7.6 2002 7.8 6.4 9.7 12.1 12.0 12.3 12.8 11.4 13.3 11.4 8.3 7.8 2003 7.3 11.3 11.0 13.0 12.8 14.0 11.7 12.2 10.6 11.4 8.7 9.8 2004 8.5 10.3 11.7 13.7 12.6 10.0 11.6 13.2 12.1 11.6 10.0 10.2 2005 8.8 9.7 11.2 11.8 12.6 14.0 13.0 12.2 12.2 11.4 11.0 9.0 2006 6.7 10.7 12.1 13.6 12.9 15.5 10.9 13.8 11.9 9.8 10.5 7.2 2007 9.3 10.6 11.3 14.3 14.7 13.8 15.1 14.0 12.5 10.8 11.3 8.5 2008 6.3 10.7 11.5 13.5 12.4 11.3 14.4 10.1 9.0 11.2 9.4 7.6 2009 6.8 9.4 11.6 14.0 15.2 13.9 11.4 12.4 12.3 10.9 11.7 6.0 2010 7.9 8.0 11.9 12.7 15.2 16.0 11.0 11.2 15.3 11.3 8.1 8.3 2011 6.3 10.1 13.2 11.2 11.6 11.4 11.4 14.5 11.7 7.4 8.2 4.8 2012 6.6 10.2 11.8 12.4 12.7 13.8 13.7 12.2 12.5 11.2 10.2 5.6 2013 6.6 9.0 10.1 11.6 11.9 13.8 14.0 12.0 12.3 10.6 9.3 4.6 2014 8.3 9.6 10.6 11.5 14.5 11.5 12.7 12.8 13.4 11.9 9.7 7.5 2015 7.7 9.6 10.1 11.9 9.7 14.3 12.3 11.9 10.6 10.7 11.2 8.0 2016 7.8 9.3 11.5 12.3 11.0 10.4 12.2 13.0 11.3 10.5 12.7 9.6 2017 7.6 7.5 11.8 11.5 14.0 10.5 13.2 11.7 11.3 8.4 7.4 6.6 2018 5.9 9.4 12.1 12.8 12.8 15.1 14.7 12.6 12.1 11.8 7.5 6.3 2019 7.4 10.6 11.0 10.7 12.5 12.4 10.1 12.9 11.0 11.3 8.6 5.5 2020 6.1 8.5 11.4 10.1 11.5 -999.0 12.0 14.3 12.2 9.9 9.2 7.0 2021 7.2 9.1 12.8 12.1 11.9 12.0 12.2 12.9 11.9 11.0 9.2 8.3 2022 8.6 9.7 11.5 12.5 13.3 15.0 13.7 11.1 8.8 12.5 7.9 8.6 2023 6.7 8.9 10.6 13.5 11.7 13.3 10.7 13.4 13.5 11.3 8.9 8.1