Year	Percent
1991	34.999
1992	36.426
1993	38.958
1994	51.95
1995	51.12
1996	69.111
1997	53.631
1998	50.852
1999	46.351
2000	39.011
2001	38.42
2002	38.946
2003	38.259
2004	40.471
2005	39.767
2006	40.537
2007	39.946
2008	40.014
2009	30.562
2010	29.815
2011	28.581
2012	30.421
2013	28.8
2014	23.062
2015	25.219
2016	25.425
2017	25.347
2018	25.358
2019	25.37
2020	25.357
2021	25.369
2022	25.404