Year	Percent
1990	27.618
1991	27.68
1992	27.719
1993	27.752
1994	27.751
1995	27.709
1996	27.773
1997	27.821
1998	27.832
1999	27.821
2000	27.784
2001	27.812
2002	27.83
2003	27.805
2004	27.775
2005	27.74
2006	27.725
2007	27.688
2008	27.66
2009	27.588
2010	27.526
2011	27.494
2012	27.447
2013	27.378
2014	27.291
2015	27.199
2016	27.15
2017	27.118
2018	27.086
2019	27.054
2020	27.022
2021	26.991
2022	26.959
2023	26.927
2024	26.895
2025	26.863
2026	26.831
2027	26.799
2028	26.767
2029	26.736
2030	26.704