Year	Percent
1990	7.198
1991	7.166
1992	7.2
1993	7.2
1994	7.511
1995	7.834
1996	8.17
1997	8.519
1998	8.882
1999	9.258
2000	9.649
2001	10.054
2002	10.474
2003	10.91
2004	11.362
2005	11.829
2006	12.314
2007	12.815
2008	13.334
2009	13.87
2010	16.29
2011	16.92
2012	17.64
2013	17.45
2014	18.53
2015	18.14
2016	17.66
2017	17.896
2018	18.132
2019	18.368
2020	18.604
2021	18.84
2022	19.076
2023	19.313
2024	19.549
2025	19.785
2026	20.021
2027	20.257
2028	20.493
2029	20.729
2030	20.965