Year years 1960 51.114 1961 51.513 1962 52.066 1963 52.623 1964 53.11 1965 53.581 1966 54.038 1967 54.459 1968 54.873 1969 55.242 1970 55.601 1971 55.965 1972 56.287 1973 56.55 1974 56.77 1975 56.95 1976 57.086 1977 57.206 1978 57.28 1979 57.388 1980 57.485 1981 57.627 1982 57.889 1983 58.235 1984 58.583 1985 58.853 1986 58.981 1987 59.027 1988 59.143 1989 59.334 1990 59.457 1991 59.714 1992 60.002 1993 60.29 1994 60.462 1995 60.756 1996 61.075 1997 61.307 1998 61.402 1999 61.454 2000 61.253 2001 61.577 2002 61.619 2003 61.663 2004 61.715 2005 61.765 2006 61.811 2007 61.745 2008 61.664 2009 61.672 2010 61.668 2011 61.687 2012 61.827 2013 61.924 2014 62.106 2015 62.307 2016 62.559 2017 62.77 2018 62.996 2019 63.233 2020 63.426 2021 63.692 2022 63.546