Year	Number
1971	3767939
1972	3941235
1973	4115217
1974	4262971.5
1975	4342695
1976	4474943.5
1977	4678878.5
1978	4808658.5
1979	4833886
1980	4843443.5
1981	4895818.5
1982	4938671
1983	5066273.5
1984	5197313.5
1985	5411440.5
1986	5649637.5
1987	5902047.5
1988	6111796
1989	6270410
1990	6500241
1991	6685988.5
1992	6830670.5
1993	6982289.5
1994	7149540
1995	7342974.5
1996	7659205.5
1997	7927913
1998	8253002.5
1999	8562174
2000	8820799
2001	8872409
2002	9453036
2003	9881879
2004	10078970
2005	10445365
2006	10443440
2007	10957316
2008	11448225
2009	11779177
2010	12110648
2011	12406909
2012	12468480
2013	12577532
2014	12846566
2015	13135032
2016	13584422
2017	13967886
2018	14639777
2019	15301000
2020	15455613
2021	16244572
2022	16592328