Year years 1960 38.334 1961 38.605 1962 38.996 1963 39.294 1964 39.833 1965 40.296 1966 40.764 1967 41.23 1968 41.603 1969 42.195 1970 42.522 1971 43.024 1972 43.442 1973 43.831 1974 44.275 1975 44.891 1976 45.34 1977 45.89 1978 46.462 1979 47.093 1980 47.829 1981 48.3 1982 48.953 1983 49.551 1984 50.365 1985 51.026 1986 51.676 1987 52.53 1988 53.099 1989 54.08 1990 54.751 1991 55.412 1992 56.421 1993 57.053 1994 57.873 1995 58.564 1996 59.063 1997 59.706 1998 60.186 1999 60.764 2000 61.199 2001 61.779 2002 61.362 2003 62.376 2004 62.886 2005 63.525 2006 64.015 2007 64.503 2008 64.664 2009 64.985 2010 65.093 2011 65.559 2012 65.736 2013 66.191 2014 66.357 2015 65.835 2016 67.031 2017 67.174 2018 67.231 2019 67.755 2020 67.345 2021 66.574 2022 68.608