Year	Percent
1990	29.481
1991	29.492
1992	29.5
1993	29.508
1994	29.51
1995	29.517
1996	29.528
1997	29.538
1998	29.545
1999	29.555
2000	29.56
2001	29.567
2002	29.57
2003	29.572
2004	29.571
2005	29.57
2006	29.568
2007	29.565
2008	29.563
2009	29.564
2010	29.558
2011	29.554
2012	29.547
2013	29.54
2014	29.532
2015	29.524
2016	29.52
2017	29.518
2018	29.517
2019	29.516
2020	29.514
2021	29.513
2022	29.511
2023	29.51
2024	29.508
2025	29.507
2026	29.505
2027	29.504
2028	29.502
2029	29.501
2030	29.499