Year	Percent
1971	0.99893
1972	0.98888
1973	0.98953
1974	0.99655
1976	1.01228
1984	0.99963
1985	1.00974
1986	1.01562
1987	1.00797
1999	0.98485
2001	0.99386
2005	1.01374
2007	0.98794
2008	1.0156
2009	1.00858
2010	1.02783
2011	1.02846
2012	1.03242