Year	Percent
1990	92.639
1991	92.717
1992	92.187
1993	92.028
1994	91.726
1995	91.362
1996	90.051
1997	87.218
1998	86.366
1999	85.438
2000	84.732
2001	82.671
2002	81.805
2003	81.155
2004	79.624
2005	78.923
2006	78.525
2007	77.767
2008	76.928
2009	76.931
2010	77.52
2011	77.292
2012	76.923
2013	77.209
2014	77.332
2015	77.865
2016	78.552
2017	78.347
2018	78.158
2019	77.995
2020	77.854
2021	77.692
2022	77.525
2023	77.378
2024	77.265
2025	77.186
2026	77.178
2027	77.171
2028	77.164
2029	77.138
2030	77.079