Year	Number
1990	27005
1991	22690
1992	22310
1993	22014
1994	21811
1995	21581
1996	21336
1997	21016
1998	20606
1999	20141
2000	19628
2001	19118
2002	18647
2003	21116
2004	17862
2005	17561
2006	17301
2007	16997
2008	16720
2009	16545
2010	16391
2011	16725
2012	18159
2013	18431
2014	18195
2015	18247
2016	17474
2017	17670
2018	18153
2019	17040
2020	16479
2021	16757
2022	16546