Year	Number
1985	22780
1986	23112
1987	25468
1988	27137
1989	27044
1990	20935
1991	21362
1992	63372
1993	69868
1994	55465
1995	50169
1996	51309
1997	49480
1998	52780
1999	58619
2000	73673
2001	82491
2002	86846
2003	106756
2004	118608
2005	149282
2006	184765
2007	222579
2008	269669
2009	300185
2010	370150
2011	492097
2012	612400
2013	788054
2014	881164
2015	1042471
2016	1292912
2017	1334148