Year	Percent
1960	1.72028
1961	1.76354
1962	1.80383
1963	1.8439
1964	1.88399
1965	1.92123
1966	1.88967
1967	1.83652
1968	1.87604
1969	2.03704
1970	2.23694
1971	2.58075
1972	2.78776
1973	2.46552
1974	1.48426
1975	0.1145
1976	-1.52087
1977	-2.92048
1978	-3.55875
1979	-2.97361
1980	-1.40424
1981	0.5841
1982	2.24614
1983	3.29024
1984	3.46757
1985	3.08436
1986	2.55193
1987	2.21704
1988	2.11494
1989	2.34741
1990	2.76266
1991	3.28073
1992	3.5928
1993	3.43844
1994	2.73023
1995	1.70859
1996	0.51151
1997	-0.44877
1998	-0.78288
1999	-0.22274
2000	0.96123
2001	2.37226
2002	3.44614
2003	3.92977
2004	3.66274
2005	2.94468
2006	2.13366
2007	1.54735
2008	1.22601
2009	1.28206
2010	1.59614
2011	1.9573
2012	2.20585
2013	2.35846
2014	2.37357
2015	2.29557
2016	2.20709
2017	2.15526