Year Number 1976 53000 1977 55000 1978 60000 1979 65000 1980 75000 1981 103100 1982 104000 1983 122200 1984 127000 1985 128200 1986 150000 1987 174000 1988 176200 1989 176700 1990 176900 1991 96000 1992 100000 1993 100000 1994 118300 1995 124200 1996 129200 1997 237000 1998 236100 1999 252300 2000 263547 2001 242799 2002 236577 2003 252751 2004 560000 2005 690000 2006 753511 2007 793153 2008 807957 2009 776469 2010 570553 2011 620394.751123946 2012 597982.600368215 2013 600000 2014 590304 2015 548908 2016 565810 2017 336718 2018 561944 2019 675482 2020 226645.666 2021 76354.068