Year	Number
1960	14551
1961	15145
1962	15800
1963	16504
1964	17226
1965	17938
1966	18639
1967	19335
1968	20042
1969	20773
1970	21611
1971	22609
1972	23697
1973	24823
1974	25967
1975	27110
1976	28230
1977	29337
1978	30457
1979	31581
1980	32621
1981	33550
1982	34464
1983	35399
1984	36354
1985	37345
1986	38357
1987	39367
1988	40332
1989	41207
1990	42030
1991	42867
1992	43717
1993	44572
1994	45468
1995	46402
1996	47339
1997	48261
1998	49176
1999	50089
2000	50759
2001	51095
2002	51326
2003	51543
2004	51775
2005	52035
2006	52309
2007	52608
2008	52912
2009	53160
2010	53298
2011	53322
2012	53280
2013	53175
2014	53014
2015	52808
2016	52557
2017	52279
2018	51980
2019	51659
2020	51673
2021	52022
2022	52317
2023	52561