Year Number 1970 173000 1971 227100 1972 286800 1973 314100 1974 430300 1975 590400 1976 800800 1977 1093900 1978 1441000 1979 1581300 1980 1938500 1981 2300200 1982 2138400 1983 2221300 1984 1945900 1985 2575000 1986 2134000 1987 1614400 1988 995000 1989 848900 1990 964800 1991 930000 1992 646500 1993 608400 1994 664800 1995 547900 1996 221200 1997 318200 1998 313400 1999 419700 2000 507396 2001 519453 2002 520278 2003 520263 2004 540461 2005 747648 2006 1307541 2007 1363435 2008 1460900 2009 1365343 2010 4197375 2011 4793913.27416044 2012 4716148.08073056 2013 4209624 2014 4462001.62973012 2015 4613169 2016 4110075 2017 4789878 2018 7786143.99416227 2019 6539048.35309011 2020 3435350.518 2021 4486313.422