Year	Percent
1990	40.65
1991	40.656
1992	40.63
1993	41.24
1994	41.853
1995	42.468
1996	43.086
1997	43.705
1998	44.327
1999	44.951
2000	45.576
2001	46.202
2002	46.83
2003	47.033
2004	47.236
2005	47.439
2006	47.643
2007	47.846
2008	48.049
2009	48.253
2010	48.456
2011	48.66
2012	48.608
2013	48.563
2014	48.501
2015	48.395
2016	48.322
2017	48.48
2018	48.638
2019	48.797
2020	48.955
2021	49.114
2022	49.272
2023	49.43
2024	49.589
2025	49.747
2026	49.906
2027	50.064
2028	50.222
2029	50.381
2030	50.539