Year	Number
1976	4.746750071869159
1977	5.71185223835907
1978	7.739595244433041
1979	8.415528184359573
1980	6.0696956090667875
1981	4.263159543296804
1982	4.416789339949464
1983	3.4493794959332607
1984	4.020109415449112
1985	4.3337881382466446
1986	3.9359762904773996
1987	4.541610819265638
1988	3.490278399905111
1989	3.0871467815033156
1990	3.6959970127600954
1991	4.579042160284874
1992	5.832412811441055
1993	6.3010744404383665
1994	6.769498643124539
1995	6.295261559845902
1996	6.956816099084525
1997	5.6303016465232485
1998	4.856368187750828
1999	5.019660256145521
2000	4.373517565039231
2001	4.22154675509113
2002	4.728095060444536
2003	5.290934489417517
2004	5.041033929080702
2005	4.8138012398368675
2006	5.266024349570589
2007	7.9040990955525725
2008	6.537961758116711
2009	9.77804431596131
2010	8.240574145496176
2011	8.167119667367405
2012	8.98759057971021
2013	8.648074995657824
2014	8.689516614555767
2015	10.493129668495964
2016	11.519123382148345
2017	10.448516923747093
2018	9.356097065350871
2019	8.965717815867169
2020	11.292006878309229
2021	8.37533832126393
2022	6.384366359156954
2023	7.099973431628975