Year	Number
1980	53651
1981	33945
1982	30562
1983	34848
1984	25401
1986	54350
1987	39766
1988	46452
1989	61513
1990	62849
1991	63630
1992	79798
1993	88599
1994	93177
1995	104167
1996	112633
1998	118919
1999	120789
2000	160992
2001	126881
2002	122085
2003	125453
2004	119337
2005	140683
2006	148282
2007	161110
2008	154518
2009	124007
2010	157974
2011	143791
2012	152938
2013	159533
2014	156133
2015	151302
2016	150376
2017	153575