Year	Number
1960	28017
1961	28304
1962	28629
1963	28981
1964	29367
1965	29784
1966	30220
1967	30680
1968	31167
1969	31696
1970	32284
1971	32929
1972	33635
1973	34402
1974	35234
1975	36130
1976	37093
1977	38145
1978	39282
1979	40494
1980	41779
1981	43124
1982	44536
1983	46030
1984	47608
1985	49261
1986	51014
1987	52863
1988	54811
1989	56797
1990	58832
1991	56628
1992	54267
1993	56773
1994	59313
1995	63202
1996	66836
1997	68578
1998	70568
1999	72322
2000	74235
2001	77436
2002	81117
2003	85309
2004	89546
2005	92780
2006	95748
2007	98907
2008	103050
2009	107309
2010	111402
2011	115578
2012	119508
2013	123106
2014	126247
2015	128531
2016	130375
2017	132704
2018	135641
2019	138870
2020	142113
2021	145081
2022	147850
2023	151197