Year	Percent
1990	25.347
1991	25.365
1992	25.51
1993	25.646
1994	25.667
1995	25.939
1996	25.976
1997	26.229
1998	26.401
1999	26.641
2000	26.852
2001	27.014
2002	26.465
2003	27.908
2004	28.53
2005	28.482
2006	28.126
2007	27.825
2008	27.496
2009	27.436
2010	27.383
2011	27.323
2012	26.445
2013	26.668
2014	26.711
2015	26.745
2016	26.786
2017	26.764
2018	26.736
2019	26.703
2020	26.667
2021	26.634
2022	26.6
2023	26.563
2024	26.519
2025	26.467
2026	26.416
2027	26.358
2028	26.298
2029	26.243
2030	26.198
