Year	Number
1996	1.319948554039
1998	1.16445672512054
2000	1.34945940971375
2002	1.59024393558502
2003	1.61025357246399
2004	1.66940915584564
2005	1.5328688621521
2006	1.43954706192017
2007	1.57299721240997
2008	1.63588404655457
2009	1.64970362186432
2010	1.65624058246613
2011	1.89224195480347
2012	1.90003883838654
2013	1.8954666852951
2014	1.8051632642746
2015	1.80380487442017
2016	1.84277331829071
2017	1.78961646556854
2018	1.82550489902496
2019	1.79326152801514
2020	1.67861640453339
2021	1.74532163143158
2022	1.68157696723938