Year	Percent
1990	70.233
1991	70.492
1992	70.527
1993	70.616
1994	70.506
1995	70.538
1996	70.552
1997	70.455
1998	70.355
1999	70.09
2000	69.927
2001	69.682
2002	69.326
2003	69.053
2004	68.953
2005	68.876
2006	68.509
2007	68.279
2008	68.085
2009	67.881
2010	67.378
2011	67.375
2012	67.027
2013	66.709
2014	66.391
2015	66.1
2016	65.757
2017	65.47
2018	65.195
2019	64.894
2020	64.549
2021	64.131
2022	63.681
2023	63.216
2024	62.747
2025	62.284
2026	61.798
2027	61.329
2028	60.875
2029	60.448
2030	60.049