Year	Percent
1991	41.912
1992	43.948
1993	41.782
1994	39.387
1995	41.231
1996	44.003
1997	45.049
1998	46.271
1999	47.082
2000	43.188
2001	44.618
2002	45.642
2003	45.312
2004	44.262
2005	46.248
2006	45.849
2007	45.245
2008	47.667
2009	48.022
2010	48.252
2011	47.751
2012	47.092
2013	45.991
2014	46.072
2015	44.66
2016	44.402
2017	44.216
2018	44.102
2019	43.903
2020	43.752
2021	43.612
2022	43.486