Year	Number
1960	12426
1961	12749
1962	12995
1963	13186
1964	13338
1965	13471
1966	13652
1967	13901
1968	14175
1969	14467
1970	14784
1971	15129
1972	15344
1973	15475
1974	15738
1975	16154
1976	16739
1977	17511
1978	18485
1979	19676
1980	21098
1981	23025
1982	25344
1983	27670
1984	29983
1985	32259
1986	34469
1987	36594
1988	38607
1989	40513
1990	42416
1991	44500
1992	46780
1993	49151
1994	51588
1995	54110
1996	56725
1997	59436
1998	62225
1999	65104
2000	68080
2001	71344
2002	74850
2003	78335
2004	81799
2005	85266
2006	88806
2007	92481
2008	96327
2009	100369
2010	104650
2011	109048
2012	113432
2013	117993
2014	122562
2015	127074
2016	131812
2017	136842
2018	142249
2019	147994
2020	154115
2021	160155
2022	166730
2023	174515