Year	Number
1985	30994
1986	28393
1987	32405
1988	29769
1989	32893
1990	36288
1991	36982
1992	55364
1993	55145
1994	60458
1995	63879
1996	79028
1997	102543
1998	119485
1999	116523
2000	119366
2001	125710
2002	127098
2003	134071
2004	157281
2005	188729
2006	201100
2007	217671
2008	229236
2009	202330
2010	221331
2011	244668
2012	253558
2013	262639
2014	271181
2015	282469
2016	273585
2017	271319