Year	Percent
1990	24.994
1991	25.255
1992	25.441
1993	25.44
1994	25.569
1995	25.346
1996	25.225
1997	25.274
1998	25.264
1999	25.235
2000	25.076
2001	24.952
2002	24.885
2003	24.805
2004	24.711
2005	24.602
2006	24.525
2007	24.384
2008	24.315
2009	24.342
2010	24.305
2011	24.171
2012	24.116
2013	24.09
2014	24.01
2015	23.914
2016	23.8
2017	23.744
2018	23.677
2019	23.589
2020	23.472
2021	23.381
2022	23.266
2023	23.139
2024	23.025
2025	22.933
2026	22.914
2027	22.917
2028	22.93
2029	22.939
2030	22.933