Year	Percent
1971	104.02226
1972	100.16142
1973	98.22983
1974	97.77071
1975	97.99286
1976	98.09326
1977	102.13922
1978	97.78812
1979	88.96456
1980	103.74671
1981	101.97902
1982	97.7768
1983	97.33121
1984	97.98793
1985	98.44923
1986	100.51124
1987	101.79049
1988	99.97186
1989	99.94704
1990	102.39492
1991	102.18531
1992	99.96049
1994	97.4066
1998	100.13351
1999	99.3538
2000	98.61413
2001	99.1087
2002	96.49282
2003	96.7162
2004	98.73266
2005	99.32211
2006	99.4639
2007	103.07339
2009	100.96239
2010	100.62469
2011	102.24233
2012	101.77728