Year	Number
1960	0
1965	0
1970	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	0
1993	0
1994	1100
1995	2200
1996	3700
1997	5200
1998	8000
1999	23380
2000	55057
2001	80933
2002	89900
2003	109882
2004	142190
2005	205000
2006	284661
2007	530048
2008	600000
2009	640000
2010	697920
2011	727000
2012	858809
2013	930406
2014	876176
2015	965950
2016	1044685
2017	1033915
2018	1015000
2019	1030000
2020	991500
2021	991500