Year years 1960 67.617 1961 68.031 1962 68.031 1963 68.285 1964 68.261 1965 68.493 1966 68.761 1967 68.99 1968 69.035 1969 69.047 1970 69.705 1971 69.493 1972 69.91 1973 70.35 1974 70.747 1975 71.269 1976 71.489 1977 72.173 1978 72.321 1979 72.548 1980 72.549 1981 73.089 1982 73.039 1983 73.21 1984 73.151 1985 73.253 1986 73.638 1987 74.004 1988 74.381 1989 74.735 1990 74.963 1991 75.635 1992 75.719 1993 75.94 1994 76.049 1995 76.243 1996 76.418 1997 76.464 1998 76.758 1999 76.989 2000 77.223 2001 77.59 2002 78.075 2003 77.276 2004 78.103 2005 78.527 2006 78.716 2007 78.515 2008 78.927 2009 79.07 2010 78.838 2011 79.322 2012 79.953 2013 79.927 2014 80.004 2015 80.188 2016 79.67 2017 80.085 2018 80.329 2019 80.681 2020 79.285 2021 78.647 2022 79.277