Year Number 1970 298600 1971 294600 1972 277400 1973 313700 1974 298000 1975 350900 1976 380900 1977 354500 1978 371700 1979 389800 1980 424700 1981 426700 1982 410300 1983 417900 1984 460300 1985 467200 1986 459800 1987 467000 1988 488600 1989 486000 1990 484700 1991 471100 1992 462600 1993 419800 1994 472400 1995 436800 1996 448000 1997 514100 1998 525500 1999 489200 2000 488371 2001 476764 2002 409497 2003 404867 2004 446038 2005 456226 2006 474783 2007 516809 2008 475322 2009 489833 2010 751083.9064857541 2011 846763.0595934679 2012 865954.3973417714 2013 947303.2152386172 2014 1019407.6039901314 2015 1044592 2016 1067058 2017 1166134 2018 1207023.6200312218 2019 1188184.09 2020 663178.1504 2021 747450.863