Year	Number
1960	14443
1961	14767
1962	14967
1963	15177
1964	15414
1965	15663
1966	15917
1967	16127
1968	16265
1969	16359
1970	16432
1971	16495
1972	16703
1973	17101
1974	17563
1975	18040
1976	18463
1977	18811
1978	19100
1979	19335
1980	19509
1981	19617
1982	19795
1983	20065
1984	20322
1985	20566
1986	20781
1987	20946
1988	21068
1989	21197
1990	21407
1991	21736
1992	22314
1993	23148
1994	24064
1995	25052
1996	26082
1997	27070
1998	28019
1999	28927
2000	29724
2001	30262
2002	30612
2003	30938
2004	31242
2005	31528
2006	31809
2007	32099
2008	32402
2009	32713
2010	33139
2011	33564
2012	33837
2013	34026
2014	34139
2015	34184
2016	34183
2017	34153
2018	34102
2019	34041
2020	33970
2021	34026
2022	34072
2023	33968