Year	Number
1972	42707
1973	41334
1974	59763
1975	56004
1976	57033
1977	63015
1978	73408
1979	79648
1980	82992
1981	84291
1982	87727
1983	87684
1984	87931
1985	86654
1986	90635
1987	83537
1988	85541
1989	74296
1990	57185
1991	38295
1992	21119
1993	12148
1994	45181
1995	50167
1996	54965
1997	17731
1998	85820
2000	105038
2001	78942
2002	63648
2004	86597
2005	102811
2006	112869
2007	120330
2008	132476
2009	142721
2010	139840
2011	160841
2013	99345
2014	62221
2015	62005
2016	94981