Year	Percent
1994	16.32829
1995	20.09429
1996	25.42641
1997	28.10213
1999	29.44167
2000	32.24105
2001	33.71262
2002	31.25336
2003	34.21458
2004	37.94396
2005	49.23487
2006	47.51489
2007	47.42024
2008	48.26912
2009	50.84652
2010	43.30592
2011	41.07657
2012	37.85706
2013	36.56907
2015	39.53938