Year	Number
1974	4808
1975	4988
1976	5443
1977	6626
1978	6453
1979	7088
1980	6708
1981	6656
1982	7159
1983	7497
1984	7557
1986	9615
1987	12417
1988	12508
1990	9850
1999	11602
2000	12324
2001	12595
2002	12601
2003	11585
2004	13913
2005	11097
2006	25891
2007	21614
2008	21859
2009	22075
2010	27131
2011	27807
2012	30501
2013	32596
2014	34876
2015	35824
2016	36706
2017	40467
2018	42110
2019	47578
2020	54906
2021	51676