Year	Percent
1971	27.61395
1974	29.23011
1987	50.24334
1988	51.78121
1995	61.82115
1999	60.50164
2000	63.54201
2001	65.48211
2002	68.97933
2003	77.32018
2008	95.16374
2009	96.65734
2011	93.30211
2013	99.03951
2014	100.14507
2015	100.30938
2016	98.61054