Year	Number
1976	1.6622055061237353
1977	2.114638595466001
1978	1.2960600925160588
1979	1.2681196913047854
1980	1.683432711207279
1981	1.3083664918469797
1982	1.1923499533207804
1983	0.9833553810620914
1984	0.505747965792742
1985	0.6733389272538214
1986	0.533102237574436
1987	0.8311389624055825
1988	0.4406833329304707
1989	0.6197514534443173
1990	0.7544719254005889
1991	1.346204196165809
1992	1.381355503262811
1993	1.3282374337367984
1994	1.2560794718772763
1995	0.9291089128775823
1996	0.6422443891253752
1997	0.6972619982880567
1998	0.5264645514375418
1999	0.6525624882910463
2000	0.9629213661954511
2001	0.653681222445918
2002	1.2458374065036257
2003	1.2422365929095842
2004	0.5803626787812813
2005	0.7220266635251129
2006	1.3049696202234415
2007	0.4781852713904814
2008	0.6578661341563552
2009	2.1778711753929407
2010	2.867840934550262
2011	2.657536652616047
2012	2.4019080174356504
2013	3.0705506385982524
2014	3.2840811935406413
2015	4.1678930189177255
2016	3.6883021555258773
2017	3.3414153525846126
2018	3.0000702889270263
2019	3.243873900175835
2020	4.758302797635689
2021	4.397002227705351
2022	3.2035480366409743