Year	Percent
1990	20.804
1991	22.271
1992	22.964
1993	24.334
1994	23.775
1995	23.231
1996	22.976
1997	22.041
1998	23.68
1999	24.548
2000	22.93
2001	24.286
2002	25.327
2003	24.673
2004	24.702
2005	27.37
2006	25.976
2007	24.629
2008	23.33
2009	28.296
2010	30.268
2011	30.163
2012	28.844
2013	27.693
2014	26.908
2015	26.015
2016	25.572
2017	25.917
2018	26.261
2019	26.606
2020	26.951
2021	27.295
2022	27.64
2023	27.984
2024	28.329
2025	28.674
2026	29.018
2027	29.363
2028	29.708
2029	30.052
2030	30.397