Year	Number
1980	63746
1981	64568
1982	65316
1983	61408
1984	63867
1985	65765
1986	67356
1987	70842
1988	77964
1989	85401
1990	93192
1991	90137
1992	95232
1993	103578
1994	109713
1995	126393
1996	109475
1997	122558
1998	138542
1999	153312
2000	168982
2001	181476
2002	188204
2003	192870
2004	194767
2005	213050
2006	227306
2007	246345
2008	236649
2009	229979
2010	246527
2011	252504
2012	273491
2013	292398
2014	289294
2015	292612
2016	299405
2017	297957
2018	289444
2019	289351
2020	274038