Year	Number
1961	8.943642140205855
1962	17.4321924357795
1963	9.629734735097582
1964	8.489898339544979
1965	4.904138077042146
1966	5.662675020509396
1967	7.51272142530627
1968	4.594440414091415
1969	3.20632817838879
1970	3.396526813642732
1971	10.847012068631066
1972	19.253361724047114
1973	16.261968869917997
1974	6.969152200300289
1975	4.450268532709779
1976	3.482344856856817
1977	3.8061093834434145
1978	2.3014434578284186
1979	1.8538656458470155
1980	1.8952374599328738
1981	2.488595949704621
1982	2.7229615807568046
1983	3.3445961979072596
1984	3.1405185246612466
1985	2.755949034603112
1986	2.3019982559639667
1987	2.4028449544180415
1988	2.4109008038475435
1989	2.627636086444782
1990	1.8231119479516298
1991	1.779857367696977
1992	1.6989253209326136
1993	1.7922837444838038
1994	1.4463599960138882
1995	1.7693034109110484
1996	1.9408401638109698
1997	2.053492916625929
1998	2.3659778062274297
1999	2.619982004513408
2000	2.6840769583584057
2001	4.352190823679714
2002	3.988047345789848
2003	3.829889324449065
2004	4.714175318174148
2005	5.39151451308881
2006	5.922907447210669
2007	8.217439214073496
2008	6.0217154078510635
2009	4.882302426179259
2010	5.241419719529584
2011	4.511693924184289
2012	4.976810470053783
2013	5.54254956760327
2014	5.317539300152149
2015	5.2931812142471655
2016	5.121874431629364
2017	5.576704334338508
2018	5.762071444168778
2019	5.773932133101252
2020	6.063397737543634
2021	5.767000903978264
2022	6.821029538290773
2023	6.134840525479851