Year	Number of
1980	24878
1981	28637
1982	28095
1983	26944
1984	22279
1985	26790
1986	27553
1987	27159
1988	25717
1989	26756
1990	27658
1991	27638
1992	25403
1993	27626
1994	30316
1995	29829
1996	31771
1997	30227
1998	29087
1999	29854
2000	28852
2001	28285
2002	29804
2003	26789
2004	25909
2005	26269
2006	26099
2007	25562
2008	26838
2009	27348
2010	28359
2011	28640
2012	28635
2013	29126
2014	29992
2015	30636
2016	31542
2017	30897
2018	30977
2019	30762
2020	29018