Year	Number
1981	626553
1986	597229
1991	525803
1992	494354
1993	431793
1994	425347
1995	418332
1996	422383
1997	424465
1999	423512
2000	426884
2001	434299
2002	438969
2003	442237
2004	303037
2005	307653
2006	308127
2007	313739
2008	303808
2009	336681
2010	335389
2011	309855
2012	281241
2013	271246
2014	267687
2015	265453
2016	262467
2017	263635
2018	269772