Year	Number
1974	0.16898275014588734
1975	0.08295383901912658
1976	0.13654835974579108
1977	0.09628490992195557
1978	0.18039809101738324
1979	0.06060462240235813
1980	0.4690011425889064
1981	0.2714555650541467
1982	0.43643477226043265
1983	0.15329864145689487
1984	0.9060090626286267
1985	2.442684692782788
1986	1.653714118262124
1987	9.928534730426556
1988	14.596234255801843
1989	0.8534379911943841
1991	5.837253319152585
1992	9.345150596174848
1993	6.403084755972322
1994	3.333946914286334
1995	0.7260294026750224
1996	50.79406138764945
1997	43.65023757893866
1998	74.62280585690118
1999	117.98365178106015
2000	230.30154239179984
2001	121.8081089526707
2002	14.642319196435619
2003	7.454542049403004
2004	4.623481585113495
2005	4.398958930705307
2006	2.0550839271732335
2007	1.5460025543090161
2008	1.5795295264331963
2009	0.8572400139794568
2010	0.9276191665218367
2011	1.0528700077116089
2012	0.9498289788465799
2013	1.1342177551544725
2014	1.2338426698670066
2015	1.1936046669818483
2016	1.0492614235923463
2017	1.160942319353681
2018	2.110306305221065
2019	2.1849066205940653
2020	1.9493834745358425