| Year | Value | | 2019 | 2,384 | | 2018 | 2,435 | | 2017 | 2,496 | | 2016 | 2,546 | | 2015 | 2,579 | | 2014 | 2,495 | | 2013 | 2,378 | | 2012 | 2,254 | | 2011 | 2,147 | | 2010 | 2,074 | | 2009 | 2,089 | | 2008 | 2,128 | | 2007 | 2,177 | | 2006 | 2,212 | | 2005 | 2,204 | | 2004 | 2,110 | | 2003 | 2,027 | | 2002 | 1,985 | | 2001 | 1,980 | | 2000 | 1,982 | | 1999 | 1,921 | | 1998 | 1,817 | | 1997 | 1,691 | | 1996 | 1,587 | | 1995 | 1,527 | | 1994 | 1,494 | | 1993 | 1,482 | | 1992 | 1,469 | | 1991 | 1,440 | | 1990 | 1,401 | | 1989 | 1,411 | | 1988 | 1,432 | | 1987 | 1,464 | | 1986 | 1,497 | | 1985 | 1,524 | | 1984 | 1,588 | | 1983 | 1,641 | | 1982 | 1,692 | | 1981 | 1,751 | | 1980 | 1,814 | | 1979 | 1,801 | | 1978 | 1,788 | | 1977 | 1,778 | | 1976 | 1,768 | | 1975 | 1,751 | | 1974 | 1,724 | | 1973 | 1,691 | | 1972 | 1,655 | | 1971 | 1,613 | | 1970 | 1,563 | | 1969 | 1,529 | | 1968 | 1,483 | | 1967 | 1,426 | | 1966 | 1,362 | | 1965 | 1,301 | | 1964 | 1,231 | | 1963 | 1,166 | | 1962 | 1,110 | | 1961 | 1,066 | | 1960 | 1,035 |
|