Year Number 1971 528053 1972 517494 1973 518002 1974 528074 1975 548773 1976 567331 1977 584960 1978 590268 1979 584236 1980 586230 1981 602318 1982 647100 1983 682038 1984 707729 1985 708415 1986 677387 1987 644816 1988 596965 1989 561356 1990 530993 1991 506800 1992 497771 1993 494107 1994 507617 1995 508003 1996 507238 1997 502555 1998 504046 1999 503302 2000 500946 2001 489768 2002 477865 2003 464013 2004 446610 2005 430561 2006 415858 2007 399250 2008 394246 2009 389510 2010 387969 2011 387262 2012 384834 2013 385466 2014 393020 2015 395549 2016 394433 2017 390970 2018 373837 2019 364424 2020 358766 2021 367591