Year	Percent
1990	97.262
1991	97.171
1992	97.079
1993	96.975
1994	96.865
1995	96.808
1996	96.75
1997	96.683
1998	96.415
1999	96.104
2000	96.097
2001	96.159
2002	96.068
2003	95.957
2004	95.89
2005	95.739
2006	95.58
2007	95.881
2008	95.639
2009	95.859
2010	95.559
2011	96.043
2012	96.042
2013	95.425
2014	95.662
2015	94.994
2016	94.915
2017	94.907
2018	94.899
2019	94.892
2020	94.888
2021	94.887
2022	94.887
2023	94.889
2024	94.892
2025	94.898
2026	94.905
2027	94.914
2028	94.924
2029	94.934
2030	94.943