Year	% of output
1971	13.766551757466413
1972	12.945285215366706
1973	12.439353099730459
1974	12.12912356041382
1975	11.795373827520264
1976	11.051258311589933
1977	11.387512198855699
1978	10.16318652395157
1979	10.562937907707177
1980	11.158567545772229
1981	12.544254138359964
1982	12.932240655606636
1983	11.111789635673022
1984	11.083630507304727
1985	11.849788684683135
1986	11.065126526242098
1987	11.221899578854252
1988	11.84759061367898
1989	12.629879784206278
1990	12.942324127869334
1991	12.75180835342615
1992	12.855250481695569
1993	13.44408983364413
1994	13.579735066029594
1995	14.000183910461878
1996	14.74529300974691
1997	14.550458825144933
1998	14.213621204142532
1999	14.288548900840686
2000	13.848547465661845
2001	14.057797633512159
2002	14.169122128484426
2003	12.312407659059254
2004	14.690024117887223
2005	14.921361577234734
2006	15.360625596387925
2007	15.268856117494497
2008	15.375675324434212
2009	15.85485184161581
2010	16.06027502658445
2011	15.062543146017685
2012	14.337885869777494
2013	14.300801140835311
2014	13.70565446971104