Year	Number of
1955	82590
1956	80810
1957	78590
1958	76060
1959	73600
1960	71950
1961	71450
1962	71720
1963	72680
1964	73630
1965	74160
1966	73960
1967	73580
1968	73250
1969	72970
1970	72950
1971	73310
1972	73710
1973	74210
1974	74410
1975	73970
1976	73160
1977	71920
1978	70330
1979	68790
1980	67080
1981	65350
1982	63470
1983	61520
1984	59390
1985	57200
1986	54790
1987	52250
1988	49540
1989	47100
1990	44720
1991	42550
1992	40400
1993	38550
1994	36710
1995	35150
1996	33710
1997	32500
1998	31240
1999	29950
2000	28390
2001	26550
2002	24690
2003	22520
2004	20450
2005	18700
2006	17260
2007	16040
2008	14930
2009	13900
2010	13200
2011	12380
2012	11870
2013	11310
2014	10590
2015	9980
