Year	Number
1960	19578
1961	20220
1962	20919
1963	21735
1964	22685
1965	23773
1966	24997
1967	26342
1968	27790
1969	29319
1970	30900
1971	32462
1972	33981
1973	35553
1974	37264
1975	39105
1976	41024
1977	42980
1978	44940
1979	46880
1980	48797
1981	50734
1982	52836
1983	55139
1984	57555
1985	60071
1986	62665
1987	65278
1988	67879
1989	70471
1990	73053
1991	75487
1992	77659
1993	79784
1994	82055
1995	84485
1996	87136
1997	90050
1998	93203
1999	96515
2000	99926
2001	103402
2002	106906
2003	110403
2004	113846
2005	117203
2006	120474
2007	123689
2008	126884
2009	130066
2010	133219
2011	135974
2012	138235
2013	140319
2014	142334
2015	144305
2016	146141
2017	147831
2018	149378
2019	150750
2020	152011
2021	153226
2022	154399
2023	155504