Year	Number
1980	80763
1981	75057
1982	70913
1983	69177
1984	47034
1985	74452
1986	159795
1987	192732
1988	144319
1989	150078
1990	165199
1991	146558
1992	131535
1993	151303
1994	149005
1995	159468
1996	158761
1998	170787
1999	181958
2000	218135
2001	190023
2002	199345
2003	231925
2004	240462
2005	262593
2006	263082
2007	273748
2008	294051
2009	271216
2010	322569
2011	296433
2012	305308
2013	321104
2014	330775
2015	353251
2016	377584
2017	424872
