Year	Number
1971	90770
1972	85611
1981	190251
1982	197097
1983	199776
1984	202610
1985	208923
1986	217364
1987	220317
1988	229366
1989	242126
1990	273258
1991	285557
1992	294438
1993	295972
1994	298137
1995	299056
1996	270866
1999	276582
2000	285179
2001	292759
2002	281206
2003	274801
2004	276928
2005	280030
2006	282222
2007	285033
2008	284084
2009	290569
2010	294775
2011	293861
2012	290401
2013	274393
2014	276116
2015	276487
2016	286786
2017	288074
2018	294148
2019	303911
2020	310677
2021	329126