Year	Percent
1998	19.43451
1999	19.97061
2000	20.25922
2001	20.27158
2002	20.90226
2003	21.51257
2004	21.56066
2005	21.4185
2006	21.41677
2007	21.57148
2008	21.64048
2010	23.49791
2011	24.4901
2012	24.70335
2013	24.65211
2014	23.93584