Year	Percent
1991	1.518
1992	0.41
1993	0.456
1994	0.523
1995	0.559
1996	0.558
1997	0.541
1998	0.543
1999	0.563
2000	0.513
2001	0.543
2002	0.524
2003	0.458
2004	0.483
2005	0.485
2006	0.499
2007	0.507
2008	0.527
2009	0.602
2010	0.555
2011	0.467
2012	0.483
2013	0.531
2014	0.527
2015	0.539
2016	0.517
2017	0.551
2018	0.551
2019	0.55
2020	0.55
2021	0.549
2022	0.549