Year	Percent
1991	40.591
1992	41.403
1993	41.735
1994	40.318
1995	40.062
1996	40.742
1997	39.539
1998	41.111
1999	40.692
2000	38.788
2001	39.527
2002	33.967
2003	33.973
2004	50.235
2005	24.84
2006	24.871
2007	24.803
2008	24.308
2009	26.667
2010	25.746
2011	25.644
2012	25.574
2013	26.332
2014	26.625
2015	28.145
2016	28.623
2017	29.045
2018	29.034
2019	29.02
2020	29.006
2021	28.99
2022	28.974
