Year	Percent
1990	14.29
1991	13.757
1992	13.242
1993	12.742
1994	12.259
1995	11.792
1996	11.34
1997	11.528
1998	11.718
1999	11.912
2000	12.108
2001	12.307
2002	12.508
2003	12.713
2004	12.92
2005	13.13
2006	13.343
2007	13.559
2008	13.778
2009	14
2010	13.969
2011	13.944
2012	13.931
2013	13.87
2014	13.796
2015	13.729
2016	13.659
2017	13.794
2018	13.928
2019	14.062
2020	14.197
2021	14.331
2022	14.466
2023	14.6
2024	14.734
2025	14.869
2026	15.003
2027	15.138
2028	15.272
2029	15.406
2030	15.541