Year	Percent
2005-01-01	51.9337896178848
2006-01-01	53.1673864100357
2007-01-01	54.5651469677316
2008-01-01	57.3489186410071
2009-01-01	58.3604255394557
2010-01-01	63.1648125607566
2011-01-01	65.4865075695224
2012-01-01	65.7802351395536
2013-01-01	66.4586615793059
2014-01-01	67.2895673313320
2015-01-01	67.5463523031352
2016-01-01	68.1536176685598
2017-01-01	68.7471033109875