Year	Number
1977	0.48783678589886387
1978	0.4436126149738219
1979	0.9170725560114064
1980	0.970514529980692
1981	0.5048764719358682
1982	0.44502214865025713
1983	0.9089242028129242
1984	0.34676885339055197
1985	0.6309224913470162
1986	0.28943840434320484
1987	0.3232423248539776
1988	0.857504270095137
1989	0.42411704402058764
1990	0.14628793257108594
1991	0.24083064018910313
1992	0.13136552038779584
1993	0.070292900912138
1994	0.08762445430136433
1995	0.090767573006064
1996	0.05692281646932857
1997	0.03668004942142286
1998	0.042813613113719146
1999	0.05514238802821692
2000	0.8729375297318768
2001	1.234147436614602
2002	2.173337257452588
2003	1.9743227709030002
2004	2.235883610850118
2005	2.308993569957105
2006	4.135353513080473
2007	5.3627205664566455
2008	4.408861874661538
2009	6.42071780511389
2010	6.514755701133001
2011	4.41639367786274
2012	4.604902478636925
2013	4.327249495030843
2014	3.6118883277236526
2015	5.046588285707454
2016	3.408705943570979
2017	4.72598094872677
2018	4.428228039987665
2019	4.393728700767807
2020	5.7882625091073105
2021	5.212840748867841
2022	5.585373215738038