Year	Number
1990	50770
1991	49186
1992	48786
1993	48476
1994	47457
1995	46614
1996	46018
1997	45504
1998	45217
1999	45060
2000	44717
2001	43108
2002	39947
2003	36531
2004	33179
2005	29638
2006	26786
2007	24885
2008	27437
2009	21884
2010	20751
2011	19793
2012	18904
2013	18232
2014	17710
2015	17192
2016	16790
2017	16575
2018	16486
2019	16487
2020	16419
2021	16233
2022	16093