| Year | Value | | 2022 | 13,809 | | 2021 | 13,288 | | 2020 | 12,850 | | 2019 | 12,508 | | 2018 | 12,244 | | 2017 | 12,038 | | 2016 | 11,879 | | 2015 | 11,727 | | 2014 | 11,521 | | 2013 | 11,234 | | 2012 | 10,861 | | 2011 | 10,432 | | 2010 | 9,982 | | 2009 | 9,553 | | 2008 | 9,169 | | 2007 | 8,831 | | 2006 | 8,533 | | 2005 | 8,324 | | 2004 | 8,263 | | 2003 | 8,297 | | 2002 | 8,312 | | 2001 | 8,264 | | 2000 | 8,159 | | 1999 | 8,003 | | 1998 | 7,788 | | 1997 | 7,554 | | 1996 | 7,349 | | 1995 | 7,146 | | 1994 | 6,997 | | 1993 | 6,923 | | 1992 | 7,175 | | 1991 | 7,383 | | 1990 | 7,191 | | 1989 | 6,945 | | 1988 | 6,695 | | 1987 | 6,450 | | 1986 | 6,210 | | 1985 | 5,977 | | 1984 | 5,749 | | 1983 | 5,529 | | 1982 | 5,317 | | 1981 | 5,113 | | 1980 | 4,918 | | 1979 | 4,731 | | 1978 | 4,551 | | 1977 | 4,382 | | 1976 | 4,222 | | 1975 | 4,068 | | 1974 | 3,920 | | 1973 | 3,783 | | 1972 | 3,652 | | 1971 | 3,528 | | 1970 | 3,410 | | 1969 | 3,300 | | 1968 | 3,195 | | 1967 | 3,097 | | 1966 | 3,005 | | 1965 | 2,917 | | 1964 | 2,833 | | 1963 | 2,755 | | 1962 | 2,680 | | 1961 | 2,610 | | 1960 | 2,545 |
|