Year	Number
1970	804919
1971	807523
1972	794842
1973	843979
1974	823463
1975	827530
1976	809601
1977	831127
1978	774945
1979	752230
1980	748607
1981	791443
1982	789811
1983	839437
1984	850473
1985	876329
1986	805461
1987	744266
1988	730171
1989	755698
1990	793024
1991	828950
1992	912061
1993	806306
1994	753115
1995	674967
1996	581514
1997	484101
1998	252278
1999	249081
2000	286812
2001	261139
2002	281274
2003	293069
2004	311200
2005	242421
2006	236841
2007	209268
2008	177610
2009	190952
2010	183140
2011	168709
2012	144998
2013	143804
2014	191156
2015	178576
2016	197205
2017	229346
2018	304364