Year	Percent
1990	5.582
1991	5.8
1992	6.025
1993	6.259
1994	6.501
1995	6.751
1996	7.011
1997	7.28
1998	7.558
1999	7.846
2000	8.144
2001	8.452
2002	8.771
2003	9.101
2004	9.441
2005	9.794
2006	10.157
2007	10.533
2008	10.921
2009	11.321
2010	10.81
2011	11
2012	10.44
2013	9.55
2014	11
2015	10.31
2016	10.73
2017	10.841
2018	10.953
2019	11.064
2020	11.176
2021	11.287
2022	11.399
2023	11.51
2024	11.622
2025	11.733
2026	11.845
2027	11.956
2028	12.068
2029	12.179
2030	12.291
