Year | Value | 2021 | 50,910 | 2020 | 50,910 | 2019 | 50,840 | 2018 | 50,840 | 2017 | 50,810 | 2016 | 50,730 | 2015 | 50,730 | 2014 | 50,730 | 2013 | 50,730 | 2012 | 50,730 | 2011 | 50,709 | 2010 | 50,500 | 2009 | 50,890 | 2008 | 51,320 | 2007 | 51,750 | 2006 | 52,080 | 2005 | 52,500 | 2004 | 52,250 | 2003 | 52,170 | 2002 | 51,990 | 2001 | 51,750 | 2000 | 51,410 | 1999 | 50,180 | 1998 | 49,130 | 1997 | 48,080 | 1996 | 46,540 | 1995 | 45,530 | 1994 | 42,200 | 1993 | 41,900 | 1992 | 41,200 | 1991 | 40,600 | 1990 | 40,250 | 1989 | 39,930 | 1988 | 39,400 | 1987 | 38,890 | 1986 | 38,570 | 1985 | 38,550 | 1984 | 38,830 | 1983 | 38,300 | 1982 | 38,290 | 1981 | 38,270 | 1980 | 37,450 | 1979 | 37,400 | 1978 | 37,350 | 1977 | 37,300 | 1976 | 36,300 | 1975 | 36,300 | 1974 | 36,300 | 1973 | 36,200 | 1972 | 36,100 | 1971 | 36,050 | 1970 | 35,850 | 1969 | 35,850 | 1968 | 35,800 | 1967 | 35,800 | 1966 | 35,800 | 1965 | 35,180 | 1964 | 34,880 | 1963 | 34,680 | 1962 | 34,300 | 1961 | 34,300 |
|