Year	Number
1990	18764
1991	18513
1992	18305
1993	17859
1994	17381
1995	16985
1996	16538
1997	16135
1998	15734
1999	15406
2000	15118
2001	14800
2002	14476
2003	14159
2004	13839
2005	13466
2006	12736
2007	12227
2008	11854
2009	11347
2010	10664
2011	9949
2012	9467
2013	9113
2014	8854
2015	8470
2016	8115
2017	7905
2018	7542
2019	7219
2020	6994
2021	6694
2022	6456