Year	Percent
1990	36.547
1991	37.15
1992	37.828
1993	38.062
1994	37.83
1995	38.002
1996	38.27
1997	39.238
1998	40.231
1999	41.271
2000	42.361
2001	43.451
2002	44.569
2003	45.7
2004	46.818
2005	47.907
2006	49.268
2007	50.634
2008	52.012
2009	53.407
2010	54.814
2011	55.863
2012	56.892
2013	56.174
2014	55.487
2015	54.841
2016	54.931
2017	55.468
2018	56.021
2019	56.598
2020	57.201
2021	57.805
2022	58.429
2023	59.058
2024	59.669
2025	60.249
2026	60.788
2027	61.302
2028	61.799
2029	62.289
2030	62.778