Year	Number
1971	3415650
1972	3230880
1973	3445528
1974	3646421
1975	4119157
1976	4468299
1977	4768588
1978	5020686
1979	4395000
1980	4929000
1981	4799000
1982	5283377
1983	5592808
1984	5994403
1985	6343300
1986	6788323
1987	7232820
1988	7757707
1989	8262441
1990	8817145
1991	9369646
1992	9787593
1993	9937369
1994	9862817
1995	9745600
1996	9593784
1997	9238393
1998	9065214
1999	8667147
2000	8287537
2001	7968437
2002	7513015
2003	7028924
2004	6647917
2005	6206718
2006	6006553
2007	5827851
2008	5725620
2009	5695590
2010	5629585
2011	5678434
2012	5746859
2013	7857540
2014	7441078
2015	7670175
2016	8006278
2017	8171667
2019	8533709
2020	8670052