Year	Percent
1990-01-01	23.4085
1991-01-01	24.0645
1992-01-01	24.3805
1993-01-01	26.6429
1994-01-01	31.5033
1995-01-01	35.5947
1996-01-01	37.9404
1997-01-01	39.9460
1998-01-01	43.0442
1999-01-01	43.3550
2000-01-01	42.4084
2001-01-01	44.0128
2002-01-01	48.4971
2003-01-01	54.7318
2004-01-01	56.5182
2005-01-01	53.1800
2006-01-01	51.1848
2007-01-01	52.6017
2008-01-01	52.4233
2009-01-01	58.1421
2010-01-01	64.1347
2011-01-01	63.0899