Year	Percent
1990	6.829
1991	6.825
1992	6.823
1993	6.823
1994	6.824
1995	6.825
1996	6.826
1997	6.827
1998	6.828
1999	6.83
2000	6.832
2001	6.833
2002	6.834
2003	6.835
2004	6.837
2005	7.703
2006	7.446
2007	7.179
2008	6.932
2009	7.063
2010	7.025
2011	6.98
2012	7.018
2013	6.905
2014	6.85
2015	6.711
2016	6.583
2017	6.588
2018	6.594
2019	6.6
2020	6.606
2021	6.612
2022	6.617
2023	6.623
2024	6.629
2025	6.635
2026	6.641
2027	6.646
2028	6.652
2029	6.658
2030	6.664