Year	Percent
1994	4.30471
1995	4.43462
1996	3.72277
1997	3.68569
1998	4.10492
1999	5.44269
2000	7.63375
2001	8.26546
2002	8.35992
2003	7.71955
2004	8.0153
2005	7.26433
2006	6.03699
2007	4.77978
2008	3.85815
2009	4.55853
2010	6.66292
2011	6.50926
2012	6.43447
2013	6.83232
2014	6.25761
2015	4.58397
2016	3.86158
2017	3.59725