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	0
1995	0
1996	0
1997	0
1998	10000
1999	25000
2000	55000
2001	91500
2002	140000
2003	320000
2004	400000
2005	500200
2006	1200000
2007	2500000
2008	3200000
2009	3648000
2010	4000000
2011	4200000
2012	6094947
2013	7160200
2014	6769312
2015	7300000
2016	6504010
2017	6305862
2018	6602878
2019	6843380
2020	7319000
2021	7319000