Year	Percent
1990	23.682
1991	23.733
1992	23.81
1993	23.98
1994	24.002
1995	24.155
1996	24.363
1997	24.626
1998	24.854
1999	25.232
2000	25.455
2001	25.888
2002	26.274
2003	26.723
2004	27.131
2005	27.556
2006	27.744
2007	27.886
2008	28.139
2009	28.539
2010	28.758
2011	28.91
2012	29.033
2013	29.136
2014	29.211
2015	29.27
2016	29.399
2017	29.577
2018	29.756
2019	29.941
2020	30.134
2021	30.302
2022	30.479
2023	30.659
2024	30.834
2025	30.998
2026	31.125
2027	31.243
2028	31.362
2029	31.489
2030	31.631