Year	Number
1970	2069400
1971	1959100
1972	1628700
1973	2341100
1974	2462700
1975	3380700
1976	4357400
1977	4882000
1978	5843300
1979	6224900
1980	7356200
1981	7985200
1982	8118200
1983	8415100
1984	8609400
1985	9581400
1986	9424300
1987	9273300
1988	9423900
1989	9488600
1990	9658200
1991	9693300
1992	13888100
1993	11791100
1994	12261900
1995	11723800
1996	10842500
1997	11824800
1998	11636900
1999	12304200
2000	12148066
2001	12976878
2002	10439111
2003	10669835
2004	11971594
2005	13181865
2006	14641094
2007	14980619
2008	15375119
2009	14965530
2010	20918249.42916581
2011	24047302.147964593
2012	25111538.305822693
2013	24611413.68773203
2014	25043692.343339533
2015	25933086
2016	26940599
2017	25639415
2018	30098587.280617714
2019	30424229.35095083
2020	12941286.729000002
2021	16231181.411