Year	Percent
1990	3.55
1991	3.688
1992	3.864
1993	3.972
1994	4.093
1995	4.344
1996	4.539
1997	4.654
1998	4.791
1999	5
2000	5
2001	5
2002	4.7
2003	5
2004	5.1
2005	5.927
2006	6.879
2007	7.97
2008	8.94
2009	9.7
2010	10.4
2011	11.9
2012	13.7
2013	14.8
2014	16.151
2015	17.6
2016	17.816
2017	17.981
2018	18.146
2019	18.31
2020	18.475
2021	18.639
2022	18.804
2023	18.969
2024	19.133
2025	19.298
2026	19.463
2027	19.627
2028	19.792
2029	19.957
2030	20.121