Year	Number
1970	44300
1971	34000
1972	23600
1973	24300
1974	26700
1975	32000
1976	37300
1977	39900
1978	43100
1979	45000
1980	45300
1981	40600
1982	41200
1983	43800
1984	45100
1985	48200
1986	52000
1987	53800
1988	60700
1989	62500
1990	66100
1991	65700
1992	69700
1993	70300
1994	69200
1995	69400
1996	70000
1997	73300
1998	68600
1999	74400
2000	63956
2001	52616
2002	41917
2003	44731
2004	50309
2005	48905
2006	51296
2007	51029
2008	52165
2009	50939
2010	64932
2011	72695
2012	72232
2013	61820
2014	57956
2015	65749
2016	70005
2017	51019
2018	48542
2019	49749
2020	27903.88
2021	36260.96