Year	Percent
1990	38.149
1991	38.261
1992	38.378
1993	38.541
1994	38.766
1995	39.164
1996	39.279
1997	39.517
1998	39.874
1999	40.271
2000	40.627
2001	40.918
2002	41.169
2003	41.506
2004	41.824
2005	42.121
2006	42.241
2007	44.892
2008	47.571
2009	50.265
2010	52.961
2011	55.641
2012	55.726
2013	55.812
2014	55.942
2015	56.154
2016	56.365
2017	56.719
2018	57.075
2019	57.433
2020	57.791
2021	58.147
2022	58.503
2023	58.857
2024	59.209
2025	59.557
2026	59.9
2027	60.24
2028	60.575
2029	60.903
2030	61.223