Year	Number
1996	1.67779505252838
1998	1.83557486534119
2000	1.76117527484894
2002	1.67731201648712
2003	1.89488017559052
2004	1.94858276844025
2005	1.78850102424622
2006	1.93568968772888
2007	1.9852135181427
2008	1.95424950122833
2009	1.81679880619049
2010	1.87403082847595
2011	1.77572727203369
2012	1.94034564495087
2013	1.91957795619965
2014	2.05077266693115
2015	2.18110251426697
2016	2.14369583129883
2017	2.15689706802368
2018	2.22129154205322
2019	1.97553372383118
2020	1.78420507907867
2021	1.56809985637665
2022	1.58980143070221