Year	Number
1996	1.44489419460297
1998	1.30338191986084
2000	1.29281973838806
2002	1.66694176197052
2003	1.80016040802002
2004	1.84927427768707
2005	1.7701940536499
2006	1.85716688632965
2007	1.90817785263062
2008	1.88683724403381
2009	1.8766952753067
2010	1.95441770553589
2011	1.84563553333282
2012	1.7325896024704
2013	1.63623702526093
2014	1.61545813083649
2015	1.61067652702332
2016	1.51693284511566
2017	1.57189655303955
2018	1.63741767406464
2019	1.65278232097626
2020	1.61694467067719
2021	1.67969024181366
2022	1.61064612865448