Year	Number
1960	10038
1961	10685
1962	12159
1963	14509
1964	16021
1965	16220
1966	16069
1967	15956
1968	15900
1969	15918
1970	16013
1971	16192
1972	16326
1973	16405
1974	16515
1975	16612
1976	16688
1977	16726
1978	16730
1979	16708
1980	16331
1981	15660
1982	15096
1983	14644
1984	14328
1985	14164
1986	14125
1987	14149
1988	14271
1989	14490
1990	14684
1991	14863
1992	15085
1993	15317
1994	15634
1995	16356
1996	17463
1997	18726
1998	20118
1999	21605
2000	23164
2001	24760
2002	26370
2003	28065
2004	29150
2005	29617
2006	30181
2007	30773
2008	31351
2009	31959
2010	32640
2011	33339
2012	33980
2013	34562
2014	35197
2015	36052
2016	37192
2017	38577
2018	40088
2019	41609
2020	43191
2021	44541
2022	45686
2023	47285