Year	Number
1981	415228
1986	427727
1989	430800
1990	427352
1991	419153
1992	407596
1993	399586
1994	405969
1995	407338
1996	412679
1997	419256
1999	382843
2000	390938
2001	390614
2002	390917
2003	387943
2004	377055
2005	359881
2006	343474
2007	330583
2008	308763
2009	288658
2010	272106
2011	255957
2012	241653
2013	227404
2014	214579
2015	202441
2016	196664
2017	194394
2018	195480