Year	Percent
1960-01-01	31.57473
1961-01-01	30.76566
1962-01-01	29.52676
1963-01-01	28.86494
1964-01-01	28.27683
1965-01-01	27.82079
1966-01-01	27.58961
1967-01-01	28.12483
1968-01-01	28.81248
1969-01-01	28.27347
1970-01-01	27.27301
1971-01-01	27.60280
1972-01-01	30.01322
1973-01-01	34.15979
1974-01-01	36.90826
1975-01-01	32.54712
1976-01-01	28.89535
1977-01-01	27.86745
1978-01-01	26.48544
1979-01-01	25.80146
1980-01-01	26.16999
1981-01-01	29.63689
1982-01-01	32.76177
1983-01-01	33.32703
1984-01-01	35.17913
1985-01-01	36.62581
1986-01-01	39.70412
1987-01-01	58.42372
1988-01-01	74.84579
1989-01-01	81.50234
1990-01-01	87.62640
1991-01-01	87.63543
1992-01-01	72.42128
1993-01-01	57.63118
1994-01-01	57.78583
1995-01-01	61.66084
1996-01-01	67.85216
1997-01-01	77.29973
1998-01-01	84.55544
1999-01-01	89.99261
2000-01-01	98.85204
2001-01-01	103.82600
2002-01-01	105.13500
2003-01-01	106.67130
2004-01-01	111.17090
2005-01-01	119.45510
2006-01-01	128.87450
2007-01-01	140.14850
2008-01-01	151.55050
2009-01-01	163.38690