Year	Number
1976	3.509092746770497
1977	2.2951500541099015
1978	2.3304793587215884
1979	2.2938741351635685
1980	1.36864956878777
1981	0.6396742634106044
1982	0.888940134822664
1983	2.669796058823011
1984	1.6578904137299872
1985	1.4648120119970982
1986	1.7564457812223262
1987	3.3785019015332622
1988	3.6613139833915183
1989	1.5118420481032337
1990	1.9119826475959358
1991	3.9869784528449403
1992	5.162267108574865
1993	6.161061933979424
1994	6.846786203684592
1995	3.6601766405490745
1996	2.934933112145989
1997	2.406419185861965
1998	2.847088956576427
1999	2.133950145038501
2000	1.8156879354326136
2001	1.5641222938314605
2002	2.188215741181597
2003	2.7552144985093987
2004	2.8752432759152384
2005	2.170862349451883
2006	2.6135323040013954
2007	3.049792722567859
2008	2.6327143576163627
2009	5.063731301692243
2010	4.320879222216283
2011	2.783552297795056
2012	3.8512548080223974
2013	4.9097478151454474
2014	5.581685264625119
2015	6.830913990154103
2016	7.603877020991342
2017	6.768864991166755
2018	5.676269096071103
2019	5.859334504600473
2020	8.658137246262713
2021	6.290239857231336
2022	4.1813727610515965
2023	3.384646658922686