Year	Number
1960	28097
1961	25508
1962	22657
1963	19903
1964	17448
1965	15211
1966	13380
1967	11574
1968	10306
1969	8463
1970	6404
1971	4819
1972	3565
1973	3273
1974	2688
1975	2779
1976	2098
1977	1026
1978	-787
1979	-3019
1980	-3830
1981	-4815
1982	-5423
1983	-5835
1984	-6305
1985	-6410
1986	-7486
1987	-8289
1988	-9691
1989	-12238
1990	-14931
1991	-16473
1992	-17859
1993	-19258
1994	-21551
1995	-25033
1996	-29171
1997	-34189
1998	-40503
1999	-47481
2000	-44421
2001	-46128
2002	-46960
2003	-49890
2004	-40505
2005	-51269
2006	-68092
2007	-69289
2008	-70166
2009	-70926
2010	-86459
2011	-88796
2012	-91035
2013	-90637
2014	-67173
2015	-59404
2016	-51633
2017	-43868
2018	-36088
2019	-28328
2020	-14278
2021	-14278
2022	462866
2023	-125204