Year	Percent
1999-01-01	2.85946449725345
2000-01-01	2.64465357351288
2001-01-01	2.34104738731133
2002-01-01	2.39358005934616
2003-01-01	2.44962532478247
2004-01-01	2.53893466516048
2005-01-01	3.04288400516975
2006-01-01	3.19304463950477
2007-01-01	3.14878130554999
2008-01-01	3.32720466217414
2009-01-01	4.26370456032143
2010-01-01	4.81859744154286
2011-01-01	4.75834281390763
2012-01-01	4.85153102033953
2013-01-01	4.59068087167026