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	1150
1996	2719
1997	5427
1998	11060
1999	21929
2000	39900
2001	67300
2002	52250
2003	60100
2004	96000
2005	120000
2006	152000
2007	174847
2008	187146
2009	208261
2010	215890
2011	222827
2012	227601
2013	243395
2014	255123
2015	268334
2016	280111
2017	287839
2018	302673
2019	318000
2020	335000
2021	322918
2022	327667