Year	Number
1980	28683
1981	29841
1982	30668
1983	31658
1984	31984
1985	32202
1986	32169
1987	31597
1988	31912
1989	31171
1990	30724
1991	32256
1992	33919
1993	34752
1994	36715
1995	38103
1996	42322
1997	44438
1998	46523
1999	50029
2000	51736
2001	49989
2002	47598
2003	47818
2004	48448
2005	48367
2006	48012
2007	47853
2008	49240
2009	47859
2010	47047
2011	46986
2012	46620
2013	47353
2014	48154
2015	47384
2016	48480
2017	47785
2018	46617
2019	46632
2020	42260
2021	39822