Year Number 1970 1752005 1971 1876954 1972 1907160 1973 1931356 1974 1937002 1975 1899501 1976 1845796 1977 1825758 1978 1810257 1979 1804834 1980 1754075 1981 1714614 1982 1676005 1983 1647081 1984 1593266 1985 1596471 1986 1574899 1988 1543596 1989 1564047 1990 1593486 1991 1609140 1992 1583503 1993 1608204 1996 1687386 1997 1753867 1998 1777257 1999 1804612 2000 1798515 2002 1753952 2003 1713538 2004 1755997 2005 1720951 2006 1694765 2007 1679017 2008 1656810 2009 1611682 2010 1546543 2011 1520405 2012 1503898 2013 1472348 2014 1469099 2015 1477538 2016 1493732 2017 1514761 2018 1540085 2019 1552914 2020 1542099 2021 1539846 2022 1545104