Year	Number
1971	3088011
1972	3181242
1973	3292020
1974	3363384
1975	3429076
1976	3544498
1977	3644578
1978	3789530
1979	3919395
1980	4054758
1981	4195699
1982	4342470
1983	4495346
1984	4654613
1985	4522363
1986	4650756
1987	4156029
1988	4356516
1990	3429633
1991	4562430
1992	4622758
1993	4870933
1994	4939297
1995	5417506
1998	4827679
1999	4022411
2002	5455391
2007	8839888
2008	9973365
2009	10244086
2010	10572422
2011	11082501
2012	12004804
2013	12600876
2014	13534625
2015	13763196
2018	16807014
2020	18789020
2021	20169276