Year	Number
1996	1.70999908447266
1998	1.76372754573822
2000	1.81531381607056
2002	1.87056970596313
2003	1.82702851295471
2004	1.84497785568237
2005	1.81880056858063
2006	1.6867743730545
2007	1.74790990352631
2008	1.78934144973755
2009	1.81968367099762
2010	1.84410035610199
2011	1.82353007793427
2012	1.79168510437012
2013	1.80766177177429
2014	1.9021475315094
2015	1.83880865573883
2016	1.72087299823761
2017	1.69941771030426
2018	1.76834964752197
2019	1.7501482963562
2020	1.73846471309662
2021	1.74802362918854
2022	1.76914703845978