Year	Percent
1990	90.065
1991	90.059
1992	90.078
1993	90.155
1994	89.963
1995	90.016
1996	90.012
1997	89.918
1998	89.839
1999	89.899
2000	89.772
2001	89.976
2002	90.23
2003	90.169
2004	90.116
2005	90.017
2006	89.805
2007	89.699
2008	89.552
2009	89.518
2010	89.546
2011	89.581
2012	89.595
2013	89.604
2014	89.608
2015	89.733
2016	89.688
2017	89.684
2018	89.683
2019	89.675
2020	89.655
2021	89.62
2022	89.573
2023	89.522
2024	89.475
2025	89.435
2026	89.398
2027	89.368
2028	89.341
2029	89.309
2030	89.268