Year	Number
1970	10816
1971	10957
1972	11354
1973	11712
1974	12302
1975	13045
1976	13649
1977	14279
1978	14479
1979	14502
1980	16385
1981	15724
1982	17930
1983	18966
1984	19155
1986	20732
1990	25539
1991	23872
1992	26736
1993	26561
1994	28888
1995	28978
1996	31337
1997	31838
1998	32519
1999	34069
2000	32144
2004	38212
2005	42260
2006	46308
2008	38283
2009	37370
2015	39599
2016	40362
2017	43908
2019	44007
2020	52050
2021	44392
2022	41528