Year	Number
1960	9903
1961	10003
1962	10101
1963	10206
1964	10309
1965	10409
1966	10501
1967	10698
1968	10872
1969	11117
1970	11148
1971	10834
1972	10363
1973	9899
1974	10184
1975	10648
1976	11139
1977	11650
1978	12185
1979	12741
1980	13340
1981	13678
1982	13961
1983	14248
1984	14535
1985	14827
1986	15112
1987	15387
1988	15629
1989	15874
1990	16092
1991	16284
1992	16456
1993	16610
1994	16748
1995	16870
1996	16978
1997	17077
1998	17166
1999	17198
2000	17037
2001	16813
2002	16557
2003	16277
2004	15984
2005	15683
2006	15376
2007	15063
2008	14739
2009	14420
2010	14119
2011	13752
2012	13313
2013	12866
2014	12411
2015	11952
2016	11489
2017	11026
2018	10563
2019	10101
2020	9640
2021	9183
2022	8929
2023	8875