Year	Number
1974	12136
1975	12372
1976	12584
1977	12728
1978	12807
1979	12882
1980	13080
1981	12182
1982	12432
1983	14010
1984	14435
1985	13896
1986	14020
1987	14681
1988	15204
1989	15586
1990	15848
1991	15794
1992	16687
1993	17128
1994	16677
1995	17046
1996	18095
1997	18266
1998	18504
1999	18571
2000	18653
2001	18763
2002	18722
2003	18835
2004	19449
2005	20005
2006	20291
2007	20695
2008	20985
2009	21442
2010	21904
2011	22261
2012	22656
2013	22912
2014	23180
2015	23287
2016	23147
2017	23278
2018	23444
2019	23748
2020	23842
2021	23935
2022	24193