Year	Percent
1990	7.014
1991	6.914
1992	6.841
1993	6.781
1994	6.725
1995	6.628
1996	6.496
1997	6.368
1998	6.247
1999	6.134
2000	6.061
2001	5.954
2002	5.9
2003	5.876
2004	5.867
2005	5.861
2006	5.86
2007	5.86
2008	5.861
2009	5.877
2010	5.933
2011	5.962
2012	6.024
2013	6.106
2014	6.187
2015	6.257
2016	6.299
2017	6.302
2018	6.305
2019	6.308
2020	6.311
2021	6.314
2022	6.318
2023	6.321
2024	6.324
2025	6.327
2026	6.33
2027	6.333
2028	6.336
2029	6.339
2030	6.342