Year	Number
1980	160
1982	157
1983	149
1984	170
1985	2678
1986	2975
1987	3281
1988	4097
1990	4752
1991	4495
1992	4742
1993	4622
1994	4565
1995	5108
1999	4797
2001	4950
2002	3767
2005	3741
2007	4001
2008	4198
2013	2587
2014	2660
2015	2678
2016	2686
2017	2796