Year	Percent
1990	21.896
1991	23.81
1992	25.837
1993	27.977
1994	30.231
1995	32.596
1996	34.617
1997	36.699
1998	38.828
1999	40.992
2000	43.182
2001	46.051
2002	48.952
2003	51.86
2004	54.749
2005	57.599
2006	60.388
2007	59.414
2008	58.431
2009	57.44
2010	56.437
2011	55.424
2012	54.398
2013	53.36
2014	52.313
2015	49.977
2016	47.98
2017	48.48
2018	48.99
2019	49.514
2020	50.053
2021	50.61
2022	51.179
2023	51.756
2024	52.333
2025	52.906
2026	53.475
2027	54.038
2028	54.586
2029	55.11
2030	55.601