Year	Percent
1990-01-01	25.7806
1991-01-01	27.6032
1992-01-01	26.9793
1993-01-01	27.7746
1994-01-01	30.6725
1995-01-01	31.1772
1996-01-01	31.9461
1997-01-01	30.7974
1998-01-01	29.2318
1999-01-01	29.3041
2000-01-01	27.5838
2001-01-01	26.6827
2002-01-01	29.1708
2003-01-01	32.3128
2004-01-01	31.5400
2005-01-01	28.6435
2006-01-01	27.4098
2007-01-01	29.0814
2008-01-01	31.6641
2009-01-01	37.6624
2010-01-01	39.1242
2011-01-01	37.7922