Year	Percent
1980-01-01	14.48000000000000
1981-01-01	24.85540000000000
1982-01-01	24.85540000000000
1983-01-01	24.85540000000000
1984-01-01	54.10280000000000
1985-01-01	47.29090000000000
1986-01-01	34.36080000000000
1987-01-01	6.98663000000000
1988-01-01	22.29350000000000
1989-01-01	41.35430000000000
1990-01-01	34.89100000000000
1991-01-01	31.68910000000000
1992-01-01	32.61790000000000
1993-01-01	30.58530000000000
1994-01-01	45.13940000000000
1995-01-01	44.09270000000000
1996-01-01	59.06890000000000
1997-01-01	54.59880000000000
1998-01-01	68.44990000000000
1999-01-01	68.44990000000000
2000-01-01	68.44990000000000
2001-01-01	68.44990000000000
2002-01-01	68.44990000000000
2003-01-01	70.55780000000000
2004-01-01	73.53699999999999
2005-01-01	73.53699999999999
2006-01-01	73.53699999999999
2007-01-01	73.53699999999999
2008-01-01	73.53699999999999
2009-01-01	73.53699999999999
2010-01-01	73.53699999999999
2011-01-01	72.92190000000000
2012-01-01	70.96500000000000
2013-01-01	70.96500000000000
2014-01-01	70.96500000000000
2015-01-01	70.96500000000000
2016-01-01	68.81530000000000