Year	Number
1971	4095
1972	4983
1973	6091
1974	6954
1975	7811
1976	10109
1977	10347
1978	11469
1979	12911
1980	14360
1981	15901
1982	17158
1983	18864
1984	19607
1985	20979
1986	22574
1987	22444
1988	24712
1989	26659
1990	28685
1991	30031
1992	31120
1993	35013
1994	36292
1995	37635
1996	38594
1998	42438
1999	44403
2000	47413
2001	46931
2002	49042
2003	51888
2004	53953
2005	55705
2006	58787
2007	61110
2008	66084
2009	66584
2010	68924
2011	72754
2012	76841
2013	79006
2014	88466
2015	95567
2016	98149
2017	103042
2018	107537
2019	117369
2020	122537
2021	129340
2022	134736