Year	Percent
1990	8.62
1991	8.53
1992	8.28
1993	8.14
1994	9.16
1995	8.83
1996	8.58
1997	8.59
1998	8.63
1999	8.94
2000	9.38
2001	9.58
2002	9.84
2003	10.62
2004	11.1
2005	11.52
2006	11.71
2007	12.63
2008	13.27
2009	13.61
2010	13.75
2011	14.02
2012	14.43
2013	14.9
2014	15.09
2015	15.34
2016	15.53
2017	15.722
2018	15.914
2019	16.105
2020	16.297
2021	16.489
2022	16.681
2023	16.873
2024	17.065
2025	17.256
2026	17.448
2027	17.64
2028	17.832
2029	18.024
2030	18.216