Year	Number
1996	1.03622543811798
1998	1.09690153598785
2000	1.26450181007385
2002	1.33110809326172
2003	1.59025156497955
2004	1.73553156852722
2005	1.60948646068573
2006	1.91120851039886
2007	1.86417436599731
2008	1.84699952602386
2009	1.73737561702728
2010	1.67535734176636
2011	1.64496850967407
2012	1.82570827007294
2013	1.73853421211243
2014	1.82653200626373
2015	1.87842237949371
2016	1.80449724197388
2017	1.86318719387054
2018	1.86087238788605
2019	1.70707488059998
2020	1.61859095096588
2021	1.48980629444122
2022	1.59022283554077