Year	Number
1960	23785
1961	24077
1962	24339
1963	24633
1964	24975
1965	25353
1966	25778
1967	26261
1968	26805
1969	27415
1970	28024
1971	28577
1972	29082
1973	29541
1974	29963
1975	30559
1976	31371
1977	32227
1978	33101
1979	33990
1980	35000
1981	36186
1982	37410
1983	38554
1984	39601
1985	40614
1986	41698
1987	42855
1988	44046
1989	45262
1990	46512
1991	47701
1992	48949
1993	50360
1994	51903
1995	53731
1996	55964
1997	58586
1998	61431
1999	64295
2000	67076
2001	69804
2002	72579
2003	75449
2004	78399
2005	81431
2006	84573
2007	87843
2008	91221
2009	94705
2010	98179
2011	101575
2012	104965
2013	108374
2014	111798
2015	115199
2016	118550
2017	121822
2018	125017
2019	128156
2020	131001
2021	133578
2022	136113
2023	138626