Year	Percent
1981	2.17
1982	2.29
1987	1.83
1989	1.55
2003	2.4606
2004	2.7504
2010	3.3047
2011	2.8556
2012	2.3658
2013	2.6704
2014	2.3606
2015	1.989
2016	2.2278