Year	Percent
1990	10.219
1991	10.269
1992	10.422
1993	10.591
1994	10.778
1995	10.98
1996	11.201
1997	11.975
1998	12.797
1999	13.676
2000	14.619
2001	15.616
2002	16.686
2003	17.838
2004	19.081
2005	20.424
2006	19.458
2007	18.592
2008	16.301
2009	17.106
2010	16.775
2011	16.138
2012	15.541
2013	14.981
2014	14.457
2015	16.038
2016	18.122
2017	17.933
2018	17.717
2019	17.475
2020	17.211
2021	16.929
2022	16.623
2023	16.299
2024	15.964
2025	15.623
2026	15.282
2027	14.936
2028	14.587
2029	14.236
2030	13.886