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	4800
1986	15300
1987	24200
1988	33000
1989	56000
1990	79000
1991	115000
1992	166000
1993	216000
1994	321000
1995	539000
1996	1016000
1997	1717000
1998	3351000
1999	6745460
2000	10755000
2001	12200000
2002	12100000
2003	13200000
2004	14800000
2005	15834000
2006	17296000
2007	19285000
2008	20627000
2009	20149000
2010	19179000
2011	19829309
2012	19717000
2013	19467000
2014	19562000
2015	20809054
2016	20890000
2017	20532000
2018	21108000
2019	21762000
2020	21415000
2021	21888000
2022	20737000