Year	Number
1960	7.378184899057483
1961	4.328478276784227
1962	3.781607261002054
1963	3.9984774788577697
1964	3.2708403717820036
1965	3.3284958859268463
1966	3.4590966077494225
1967	6.680570218848524
1968	6.505529087828401
1969	4.113834154081787
1970	3.6479390420093045
1971	3.381390782014
1972	3.2918646546555785
1973	3.567055888369349
1974	7.958234135415197
1975	7.081476800141388
1976	4.739548170582255
1977	4.979586839161656
1978	3.8967562570034584
1979	3.671517868298627
1980	4.116045422883481
1981	2.778799729150306
1982	4.113107176916147
1983	3.6740172313474653
1984	4.5476807191728845
1985	3.432874940784725
1986	3.0793962000477486
1987	4.398759542064446
1988	5.565087704044039
1989	5.504825416694391
1990	4.823192355259112
1991	5.383504957148796
1992	5.200934605432868
1993	5.447537110300925
1994	7.680127573916416
1995	8.113039681703633
1996	5.809496013462699
1997	7.065348250440379
1998	7.312359436722295
1999	7.524255332286489
2000	9.362356756663628
2001	9.916918558208495
2002	9.31248198921247
2003	7.676885698738343
2004	7.439378393311081
2005	10.518652226012454
2006	6.895915249783374
2007	7.117352305271072
2008	5.047039528467506
2009	3.383276401247389
2010	2.065218284159975
2011	1.5582927504669135
2012	2.8114209085472885
2013	2.979389501331498
2014	3.3457132091779522
2015	2.5908748754123376
2016	1.8820750288879193
2017	2.4598386361767397
2018	2.6969452886802143
2019	2.3666686020584393
2020	2.4306461841229807
2021	2.60599467110779
2022	3.20216086573958
2023	3.447722135620838