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	841
1993	1029
1994	1251
1995	1243
1996	1200
1997	1400
1998	1454
1999	2815
2000	39830
2001	75320
2002	79400
2003	137955
2004	171656
2005	281368
2006	400000
2007	538774
2008	447769
2009	488533
2010	560397
2011	528757
2012	547047
2013	555035
2014	566905
2015	542598
2016	584659
2017	643210
2019	778000
2020	856000
2021	856000