Year	Number
1971	16860
1973	18892
1974	20511
1978	27591
1979	29156
1980	31091
1981	33594
1982	35065
1983	36256
1984	37577
1985	37839
1986	38883
1987	39818
1988	40124
1989	40366
1990	40796
1991	41451
1992	42711
1993	45182
1994	46594
1995	47368
1996	44436
1997	44382
1998	40704
1999	41727
2002	43239
2003	43477
2004	43773
2005	43533
2006	44150
2007	44416
2008	45037
2009	46191
2010	46815
2011	47300
2012	47344.55078125
2013	46645
2014	46911.80078125
2015	47000.23828125
2016	47686.13671875
2017	48296.3203125
2019	48643.1484375
2020	48410.19140625
2021	47971.640625
2022	48854.91015625