Year	Percent
1990	18.36
1991	18.45
1992	19.25
1993	18.2
1994	19.2
1995	20.16
1996	21.11
1997	22.25
1998	19.8
1999	21.5
2000	22.81
2001	22.92
2002	22.99
2003	21.51
2004	22.22
2005	22.45
2006	22.7
2007	23.34
2008	22.88
2009	22.24
2010	21.7
2011	21.82
2012	22.99
2013	23.4
2014	23.95
2015	23.41
2016	23.66
2017	23.719
2018	23.778
2019	23.837
2020	23.896
2021	23.955
2022	24.014
2023	24.073
2024	24.131
2025	24.19
2026	24.249
2027	24.308
2028	24.367
2029	24.426
2030	24.485