Year	Percent
1990	14.154
1991	14.22
1992	14.217
1993	14.482
1994	14.698
1995	14.87
1996	15.104
1997	15.42
1998	15.829
1999	16.323
2000	16.091
2001	15.827
2002	15.875
2003	16.438
2004	17.035
2005	17.66
2006	18.246
2007	17.824
2008	17.487
2009	17.12
2010	18.222
2011	19.561
2012	20.328
2013	20.297
2014	20.718
2015	22.079
2016	22.2
2017	22.252
2018	22.307
2019	22.352
2020	22.374
2021	22.232
2022	22.046
2023	21.833
2024	21.612
2025	21.396
2026	21.154
2027	20.92
2028	20.694
2029	20.472
2030	20.25