Year	Percent
1990	11.83
1991	11.83
1992	11.847
1993	11.842
1994	11.856
1995	11.841
1996	11.809
1997	11.767
1998	11.716
1999	11.642
2000	11.556
2001	11.393
2002	11.228
2003	11.049
2004	10.889
2005	10.723
2006	10.587
2007	10.482
2008	10.36
2009	10.22
2010	10.096
2011	10.003
2012	9.902
2013	9.804
2014	9.716
2015	9.636
2016	9.562
2017	9.467
2018	9.372
2019	9.277
2020	9.182
2021	9.088
2022	8.993
2023	8.898
2024	8.803
2025	8.708
2026	8.613
2027	8.518
2028	8.423
2029	8.328
2030	8.233