Year	Percent
1966-01-01	24.10610
1967-01-01	22.37320
1968-01-01	22.08460
1969-01-01	23.06680
1970-01-01	24.62190
1971-01-01	19.80380
1972-01-01	22.78780
1973-01-01	23.97130
1974-01-01	9.86276
1975-01-01	12.14830
1976-01-01	14.74050
1977-01-01	18.82120
1978-01-01	21.02150
1979-01-01	21.02150
1980-01-01	21.02150
1981-01-01	21.02150
1982-01-01	21.02150
1983-01-01	21.02150
1984-01-01	21.02150
1985-01-01	21.02150
1986-01-01	21.02150
1987-01-01	21.02150
1988-01-01	21.02150
1989-01-01	21.02150
1990-01-01	21.02150
1991-01-01	21.02150
1992-01-01	21.02150
1993-01-01	21.02150
1994-01-01	21.02150
1995-01-01	21.02150
1996-01-01	21.02150
1997-01-01	21.02150
1998-01-01	21.02150
1999-01-01	21.02150
2000-01-01	21.02150
2001-01-01	21.02150
2002-01-01	58.75830
2003-01-01	50.15010
2004-01-01	41.87670
2005-01-01	40.66270
2006-01-01	41.39750
2007-01-01	43.93570
2008-01-01	40.66740
2009-01-01	54.68760
2010-01-01	51.51520
2011-01-01	45.38170
2012-01-01	48.81350
2013-01-01	55.88450
2014-01-01	61.94720
2015-01-01	82.64160
2016-01-01	90.32560