Year	Number
1970	24462
1971	24976
1972	25761
1973	27408
1975	28492
1976	28677
1977	29017
1978	28955
1979	29249
1980	28388
1981	27675
1982	26973
1983	26939
1986	26921
1994	26681
1995	27196
1996	27011
1997	27317
1998	27439
1999	27297
2000	28026
2001	29203
2002	30530
2003	31059
2004	31175
2005	30964
2006	30516
2007	30193
2009	29663
2010	30871
2011	29860
2012	29869
2014	31350
2015	31998
2016	32629
2017	32950
2018	33123
2019	33841
2020	33950
2021	35400
2022	35334