Year	Percent
1989	30.25595
1990	51.63717
1991	32.38469
1992	31.33871
1993	17.39893
1994	21.42635
1995	24.35718
1996	28.51492
1997	31.68955
1998	40.08471
1999	48.24508
2000	57.29511
2001	77.04804
2002	95.61674
2003	114.18968
2004	112.96674
2005	107.6794
2006	109.79888
2007	101.93411
2008	82.9163
2009	70.76772
2010	65.79951
2011	62.19188
2012	67.75129
2013	70.16997
2014	66.22289
2015	66.37344
2016	67.91034