Year	Number
1971	3158
1972	4009
1974	4995
1975	4878
1976	5084
1982	8058
1984	7473
1985	6160
1986	6782
1987	8785
1988	7237
1991	10719
2000	9679
2001	9756
2002	9920
2003	9624
2004	10398
2005	9780
2007	11238
2008	11641
2009	11704
2010	11426
2011	10927
2012	10419
2013	10394
2014	10342
2015	10286
2016	10117
2017	10113
2018	9808
2019	9768
2020	9596
2021	9818
2022	9788