Year	Percent
1990	37.551
1991	38.402
1992	39.39
1993	40.492
1994	41.469
1995	42.801
1996	43.503
1997	46.456
1998	45.701
1999	44.611
2000	45.476
2001	45.231
2002	46.537
2003	46.354
2004	49.449
2005	49.973
2006	51.534
2007	52.243
2008	52.358
2009	53.579
2010	53.293
2011	53.992
2012	55.353
2013	55.713
2014	54.701
2015	55.308
2016	55.57
2017	55.799
2018	56.027
2019	56.25
2020	56.469
2021	56.685
2022	56.896
2023	57.109
2024	57.327
2025	57.555
2026	57.791
2027	58.034
2028	58.282
2029	58.53
2030	58.777