Year	Percent
1990	35.405
1991	35.434
1992	35.373
1993	35.367
1994	35.383
1995	35.4
1996	35.452
1997	35.517
1998	35.614
1999	35.701
2000	35.743
2001	35.867
2002	35.914
2003	36.003
2004	36.042
2005	38.222
2006	40.459
2007	42.756
2008	45.102
2009	47.482
2010	49.885
2011	52.608
2012	55.283
2013	57.87
2014	60.33
2015	60.374
2016	60.431
2017	60.758
2018	61.081
2019	61.403
2020	61.726
2021	62.05
2022	62.377
2023	62.708
2024	63.047
2025	63.397
2026	63.753
2027	64.119
2028	64.49
2029	64.862
2030	65.233