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	20
1995	1718
1996	3000
1997	3402
1998	5380
1999	12000
2000	15000
2001	53000
2002	61800
2003	69952
2004	98389
2005	103417
2006	109030
2007	113586
2008	120806
2009	128000
2010	131800
2012	135000
2013	138800
2014	139700
2015	141000
2019	141000
2020	141000
2021	141000