Year years 1960 45.369 1961 45.985 1962 46.434 1963 46.747 1964 46.946 1965 46.84 1966 46.619 1967 46.736 1968 46.871 1969 46.934 1970 47.805 1971 48.868 1972 50.031 1973 51.532 1974 52.478 1975 53.08 1976 48.052 1977 53.534 1978 53.245 1979 53.2 1980 52.577 1981 51.964 1982 44.787 1983 55.817 1984 56.862 1985 57.56 1986 58.114 1987 58.857 1988 59.468 1989 59.69 1990 59.622 1991 59.676 1992 59.737 1993 60.216 1994 60.473 1995 60.861 1996 61.502 1997 62.135 1998 62.713 1999 63.421 2000 63.983 2001 64.467 2002 64.887 2003 65.286 2004 65.645 2005 65.737 2006 66.307 2007 66.618 2008 66.907 2009 67.245 2010 67.55 2011 67.907 2012 68.265 2013 68.591 2014 68.882 2015 69.075 2016 69.359 2017 69.613 2018 69.896 2019 70.439 2020 68.258 2021 66.005 2022 65.697