Year	Number
1960	33704
1961	34076
1962	34827
1963	35645
1964	36434
1965	37181
1966	37742
1967	38333
1968	39154
1969	40066
1970	41009
1971	42171
1972	42792
1973	43184
1974	44274
1975	45208
1976	46001
1977	46729
1978	47077
1979	47595
1980	48293
1981	49068
1982	50072
1983	50866
1984	51482
1985	52004
1986	52158
1987	51868
1988	51207
1989	50470
1990	49976
1991	49662
1992	49536
1993	49756
1994	50003
1995	50330
1996	50910
1997	51340
1998	50689
1999	49139
2000	47394
2001	45869
2002	46094
2003	47294
2004	48401
2005	49950
2006	51491
2007	52638
2008	53354
2009	53720
2010	54397
2011	55160
2012	55419
2013	55654
2014	56028
2015	56434
2016	56786
2017	56826
2018	55872
2019	54771
2020	53882
2021	52765
2022	51682
2023	50618