Year years 1960 53.469 1961 53.939 1962 54.325 1963 54.785 1964 55.177 1965 55.522 1966 55.92 1967 56.39 1968 56.694 1969 57.173 1970 57.663 1971 58.038 1972 58.425 1973 58.832 1974 59.256 1975 59.525 1976 59.668 1977 59.877 1978 60.265 1979 60.601 1980 61.022 1981 61.452 1982 61.603 1983 61.846 1984 62.256 1985 62.475 1986 62.976 1987 63.352 1988 63.682 1989 63.787 1990 63.939 1991 64.035 1992 63.875 1993 63.804 1994 63.756 1995 63.684 1996 63.596 1997 63.646 1998 64.106 1999 64.518 2000 65.026 2001 65.156 2002 65.385 2003 65.746 2004 66.075 2005 66.068 2006 66.499 2007 66.895 2008 67.407 2009 67.958 2010 68.293 2011 68.567 2012 68.722 2013 68.74 2014 68.614 2015 68.782 2016 68.777 2017 68.916 2018 68.796 2019 69.002 2020 68.687 2021 69.264 2022 69.41