Year	Number
1960	3183
1961	3442
1962	3708
1963	3987
1964	4284
1965	4593
1966	4931
1967	5327
1968	5775
1969	6260
1970	6790
1971	7362
1972	7975
1973	8627
1974	9310
1975	10009
1976	10714
1977	11419
1978	12117
1979	12807
1980	13486
1981	14163
1982	14822
1983	15469
1984	16132
1985	16804
1986	17554
1987	18388
1988	19232
1989	20070
1990	20897
1991	21683
1992	22431
1993	23170
1994	23893
1995	24598
1996	24946
1997	24934
1998	24914
1999	24887
2000	24864
2001	25495
2002	26781
2003	28092
2004	29414
2005	30725
2006	30833
2007	29758
2008	28705
2009	27661
2010	26618
2011	26119
2012	26167
2013	26181
2014	26193
2015	26216
2016	26537
2017	27171
2018	27781
2019	28388
2020	28983
2021	29534
2022	29800
2023	29806