Year	Number
1996	0.910290777683258
1998	1.01681685447693
2000	1.14183568954468
2002	1.0168479681015
2003	1.15746104717255
2004	1.34332299232483
2005	1.28548622131348
2006	1.5849609375
2007	1.44125950336456
2008	1.45174884796143
2009	1.45010435581207
2010	1.52235090732574
2011	1.46691274642944
2012	1.40798962116241
2013	1.61111164093018
2014	1.80617105960846
2015	1.75416135787964
2016	1.78573799133301
2017	1.57973551750183
2018	1.63468813896179
2019	1.55019092559814
2020	1.54766714572906
2021	1.3627552986145
2022	1.61974680423737