Year	Number
1971	50900
1972	57240
1973	63580
1974	69920
1975	76260
1976	82600
1977	90167
1978	97734
1979	105300
1980	109700
1981	114500
1982	118600
1983	122100
1984	123200
1985	126400
1986	130000
1987	133900
1988	135700
1989	134600
1990	129100
1991	124500
1992	120600
1993	119200
1994	126400
1995	122500
1996	126200
1997	118600
1998	7600
2008	107669
2009	101768
2010	113741
2011	114039
2012	106723
2013	88257
2014	86024
2015	85086
2016	85748
2017	85034
2018	82592