Year	Percent
1990	11.496
1991	11.535
1992	11.581
1993	11.647
1994	11.724
1995	11.804
1996	11.867
1997	11.813
1998	11.799
1999	11.825
2000	11.893
2001	12.007
2002	12.162
2003	12.355
2004	12.583
2005	12.843
2006	13.133
2007	13.455
2008	13.812
2009	14.206
2010	14.379
2011	15.239
2012	16.157
2013	16.882
2014	15.34
2015	15.237
2016	15.125
2017	15.232
2018	15.311
2019	15.353
2020	15.35
2021	15.312
2022	15.235
2023	15.128
2024	15.007
2025	14.881
2026	14.757
2027	14.63
2028	14.511
2029	14.42
2030	14.369