Year years 1960 46.603 1961 47.023 1962 47.354 1963 46.189 1964 49.457 1965 46.935 1966 44.626 1967 45.056 1968 45.456 1969 45.147 1970 45.534 1971 49.646 1972 49.925 1973 53.069 1974 53.23 1975 53.377 1976 53.462 1977 53.648 1978 53.44 1979 53.559 1980 53.934 1981 54.078 1982 54.321 1983 47.45 1984 46.22 1985 46.458 1986 51.481 1987 43.441 1988 35.923 1989 49.337 1990 49.732 1991 50.213 1992 45.891 1993 46.575 1994 56.644 1995 51.991 1996 52.276 1997 52.833 1998 48.81 1999 57.015 2000 58.319 2001 58.562 2002 58.976 2003 58.2 2004 56.773 2005 57.279 2006 60.281 2007 61.256 2008 61.206 2009 62.644 2010 63.016 2011 63.246 2012 63.792 2013 63.678 2014 64.269 2015 64.659 2016 64.78 2017 65.445 2018 65.681 2019 65.876 2020 65.614 2021 65.267 2022 65.578