Year	Percent
1960-01-01	8.75421
1961-01-01	9.47020
1962-01-01	9.87500
1963-01-01	10.28790
1964-01-01	9.82280
1965-01-01	7.63675
1966-01-01	7.63675
1967-01-01	7.63675
1968-01-01	7.63675
1969-01-01	8.46017
1970-01-01	11.05350
1971-01-01	11.90520
1972-01-01	11.97680
1973-01-01	14.83940
1974-01-01	15.85840
1975-01-01	18.72080
1976-01-01	23.81710
1977-01-01	26.10080
1978-01-01	26.45940
1979-01-01	27.20210
1980-01-01	27.29990
1981-01-01	28.35670
1982-01-01	28.16040
1983-01-01	26.72030
1984-01-01	26.23380
1985-01-01	23.22860
1986-01-01	21.94020
1987-01-01	25.00270
1988-01-01	21.92170
1989-01-01	20.82990
1990-01-01	20.65520
1991-01-01	21.34220
1992-01-01	22.60160
1993-01-01	26.32490
1994-01-01	18.96490
1995-01-01	16.19760
1996-01-01	16.73060
1997-01-01	16.04780
1998-01-01	18.61400
1999-01-01	16.59460
2000-01-01	16.09850
2001-01-01	15.64970
2002-01-01	13.48930
2003-01-01	15.56640
2004-01-01	16.64270
2005-01-01	17.48600
2006-01-01	17.29350
2007-01-01	18.40310
2008-01-01	18.56680
2009-01-01	17.91030
2010-01-01	20.19050
2011-01-01	24.31860
2012-01-01	27.74870
2013-01-01	30.53980
2014-01-01	32.01820
2015-01-01	33.60840
2016-01-01	36.43020