Year	Number
1961	32212
1962	32161
1963	32141
1964	32227
1965	32512
1966	33185
1967	34200
1968	35638
1969	37432
1970	39424
1971	41530
1972	43862
1973	46548
1974	49489
1975	52624
1976	55705
1977	57937
1978	58433
1979	57438
1980	55469
1981	53066
1982	50935
1983	49518
1984	48529
1985	47754
1986	47160
1987	46897
1988	46845
1989	47248
1990	48798
1991	51893
1992	56326
1993	61875
1994	135425
1995	62965
1996	58825
1997	61072
1998	62693
1999	60575
2000	57255
2001	53586
2002	48976
2003	44258
2004	39947
2005	36136
2006	32748
2007	29820
2008	27150
2009	24863
2010	22779
2011	20827
2012	19491
2013	18508
2014	17824
2015	17325
2016	16999
2017	16772
2018	16554
2019	16278
2020	15887
2021	15542
2022	15237