year, expt yield, error:

1957	0.73	0.02
1981	0.738	0.03
1990	0.722	0.044
2001	0.734	0.028
2007	0.747	0.06
2017	0.724	0.014

1956	0.713	0


year, mean expt yield, mean expt yield +/- error

1956	0.727777
2017	0.727777
	
1956	0.717521
2017	0.717521
	
1956	0.738033
2017	0.738033


year, recom yield, recom yield +/- error

1956	0.751
2017	0.751
	
1956	0.755
2017	0.755
	
1956	0.747
2017	0.747