Year	Percent
1990	9.17
1991	8.82
1992	9.05
1993	8.1
1994	9.04
1995	9.37
1996	9.3
1997	9.76
1998	9.68
1999	9.28
2000	9.87
2001	9.89
2002	10.2
2003	10.11
2004	10.28
2005	11.35
2006	12.21
2007	13.43
2008	14.14
2009	15.26
2010	15.44
2011	16.11
2012	16.88
2013	16.82
2014	16.94
2015	16.38
2016	16.58
2017	16.833
2018	17.086
2019	17.339
2020	17.592
2021	17.845
2022	18.098
2023	18.351
2024	18.604
2025	18.857
2026	19.11
2027	19.363
2028	19.616
2029	19.869
2030	20.122