Year	Number
1971	82700
1972	95349
1973	99936
1980	5084
1981	17846
1982	41032
1983	90496
1984	153365
1985	245815
1986	311795
1987	345848
1988	352579
1989	324189
1990	288403
1991	248968
1994	285779
1995	297555
1997	327566
1998	302951
1999	308167
2000	343308
2001	389020
2002	466823
2003	545660
2004	616089
2005	708454
2006	798862
2007	856200
2008	909033
2009	918708
2010	925788
2011	910420
2012	881108
2013	849130
2014	835096
2015	839491
2016	861995
2017	905416
2018	955656