Year	Percent
1991	44.499
1992	44.521
1993	44.303
1994	44.166
1995	44.359
1996	44.213
1997	44.078
1998	44.561
1999	44.755
2000	45.477
2001	45.924
2002	44.353
2003	40.824
2004	39.612
2005	40.524
2006	42.89
2007	43.329
2008	44.986
2009	46.736
2010	46.753
2011	46.158
2012	46.185
2013	47.767
2014	49.187
2015	49.555
2016	51.234
2017	52.227
2018	52.161
2019	52.239
2020	52.37
2021	52.504
2022	52.662