Year	Percent
1971	43.4627
1972	41.41369
1973	51.02072
1974	47.06714
1999	74.19658
2000	80.55923
2001	78.4472
2002	79.16957
2003	81.36852
2004	83.61623
2007	85.21381
2008	87.62254
2009	86.12684
2010	84.79521
2017	88.36568