Year	Number
1960	27728
1961	28330
1962	28764
1963	29157
1964	29505
1965	29802
1966	30052
1967	30160
1968	30124
1969	30044
1970	29922
1971	29766
1972	29777
1973	30026
1974	30352
1975	30690
1976	30922
1977	31050
1978	31179
1979	31305
1980	31427
1981	31593
1982	31836
1983	32113
1984	32351
1985	32494
1986	32522
1987	32460
1988	32391
1989	32514
1990	33066
1991	34138
1992	35095
1993	35882
1994	36740
1995	37575
1996	38403
1997	39248
1998	40099
1999	40938
2000	41625
2001	42025
2002	42194
2003	42277
2004	42317
2005	42399
2006	42555
2007	42729
2008	42906
2009	43079
2010	43206
2011	43493
2012	43864
2013	44228
2014	44588
2015	44943
2016	45297
2017	45648
2018	45999
2019	46351
2020	46574
2021	46734
2022	46891
2023	47032