Year	Number
1960	19125
1961	19964
1962	20844
1963	21717
1964	22580
1965	23391
1966	24148
1967	24928
1968	25733
1969	26573
1970	27450
1971	28345
1972	29236
1973	30119
1974	30990
1975	31694
1976	32250
1977	32830
1978	33602
1979	34561
1980	35529
1981	36495
1982	37456
1983	38402
1984	39325
1985	40209
1986	41039
1987	41838
1988	42599
1989	43302
1990	43959
1991	44559
1992	45431
1993	46596
1994	47492
1995	47611
1996	47182
1997	46702
1998	46183
1999	45552
2000	44893
2001	44306
2002	43732
2003	43173
2004	42581
2005	41942
2006	41238
2007	40437
2008	39628
2009	38886
2010	38214
2011	37761
2012	37424
2013	37003
2014	36592
2015	36194
2016	35893
2017	35691
2018	35451
2019	35189
2020	34927
2021	34727
2022	34603
2023	34479