Year	Number
1971	25102
1972	25166
1973	25575
1974	25901
1976	25924
1977	26534
1978	27024
1980	28041
1981	27932
1982	28546
1983	29120
1984	30652
1985	30994
1986	31418
1987	32550
1988	33370
1989	34155
1990	35754
1991	37377
1992	38084
1993	39220
1994	40584
1995	41423
1996	42787
1997	42863
1999	44180
2000	44788
2001	45246
2002	44430
2003	47187
2004	48996
2005	50247
2006	51497
2007	51898
2008	51994
2009	52629
2010	52650
2011	52361
2012	53605
2013	52573
2014	51978
2015	52072
2016	52333
2017	51512
2018	50764
2019	50388
2020	49449
2021	47442
2022	45615