Year	Number
1971	17140
1972	17463
1973	19421
1974	20724
1975	22424
1976	24617
1977	25513
1978	27560
1979	32220
1980	37468
1981	47101
1982	53000
1983	58356
1984	64531
1985	69512
1986	72917
1987	74455
1988	75093
1989	73673
1990	77767
1991	86307
1992	90645
1993	97262
1994	105471
1995	113241
1996	124513
1997	133409
1998	141567
1999	170371
2000	174626
2001	181835
2002	182562
2003	196426
2004	204731
2005	205347
2006	207474
2007	218638
2008	220931
2009	224058
2010	229013
2011	228495
2012	244033
2013	255957
2014	274903
2015	293503
2016	308729
2017	329828
2018	350323
2019	374678
2020	393057
2021	401333
2022	414477
2023	428053