Year	Number
1996	2.0818977355957
1998	2.08959698677063
2000	2.13800668716431
2002	2.06836199760437
2003	1.99590289592743
2004	1.97551548480988
2005	1.96084868907928
2006	2.0405261516571
2007	2.15947222709656
2008	2.1027684211731
2009	2.12415862083435
2010	2.09006071090698
2011	2.08139801025391
2012	2.09058332443237
2013	2.01678347587585
2014	1.96069610118866
2015	1.83362650871277
2016	1.85842132568359
2017	1.74520063400269
2018	1.88895213603973
2019	1.86780214309692
2020	2.00024700164795
2021	2.00462627410889
2022	1.91718029975891