Year	Number
1960	14792
1961	16108
1962	17188
1963	17993
1964	18697
1965	19129
1966	19267
1967	18977
1968	18272
1969	17334
1970	15779
1971	14363
1972	13131
1973	12147
1974	11254
1975	10588
1976	10238
1977	10098
1978	10204
1979	10422
1980	11174
1981	11834
1982	12496
1983	13153
1984	13823
1985	14534
1986	15194
1987	15812
1988	16519
1989	17140
1990	17724
1991	18514
1992	19363
1993	20278
1994	21185
1995	22161
1996	23219
1997	24183
1998	25405
1999	26554
2000	27734
2001	29249
2002	31068
2003	33445
2004	36044
2005	39103
2006	42580
2007	46383
2008	50669
2009	55405
2010	60639
2011	65397
2012	69451
2013	72873
2014	75670
2015	77987
2016	79667
2017	80765
2018	81492
2019	81585
2020	81066
2021	80097
2022	39998
2023	39998