Year	Number
1960	15285
1961	15465
1962	15633
1963	15810
1964	16007
1965	16258
1966	16716
1967	17061
1968	17155
1969	17264
1970	17497
1971	17802
1972	18089
1973	18368
1974	18667
1975	18999
1976	19293
1977	19579
1978	20105
1979	21271
1980	22375
1981	22968
1982	23610
1983	24321
1984	25075
1985	25907
1986	26878
1987	27577
1988	27934
1989	28298
1990	28640
1991	28936
1992	29343
1993	29877
1994	30406
1995	30868
1996	31323
1997	31925
1998	32657
1999	33438
2000	34293
2001	35176
2002	36037
2003	36932
2004	37880
2005	38826
2006	39784
2007	40758
2008	41562
2009	42209
2010	42928
2011	43777
2012	44721
2013	45760
2014	46861
2015	47848
2016	48787
2017	49939
2018	51305
2019	52840
2020	54533
2021	56221
2022	58002
2023	60050