Year	Number
1975	12989
1976	13529
1977	14112
1978	15152
1979	16576
1980	17204
1981	18304
1982	21316
1983	25086
1984	28115
1985	29861
1986	32400
1987	35000
1988	36000
1989	38468
1990	40218
1991	41933
1992	54672
1993	57168
1994	58200
1995	65597
1996	70558
1997	75200
1998	93920
1999	94599
2000	95000
2001	106287
2002	110881
2003	97393
2004	99439
2005	100331
2006	130694
2007	188874
2008	255306
2009	435413
2010	539504
2011	668965
2012	737445
2013	799016
2014	1156230
2015	1050281
2016	1051073
2017	885762
2018	902253
2019	856411
2020	964378
2021	867119
2022	929007