From 1960 to 2010 the worldwide grain yield increased about 2.5 times with less than a 10% increase
AREA growing grain 1960 639 million ha 2010 680 million ha
YIELD 1960 1.29 tons/ha 2010 3.24 tons/ha
PRODUCTION 1960 824 million tons 2010 2201 million tons
[updated by Ashley 5.12.2014 -- excel data sheet from Earth Policy Inst saved in Box/World Hunger/Industrial Agr/Research folder]
Source:“World Grain Production, Area, and Yield, 1950-2012,”Earth Policy Institute Data Center, last updated January 17, 2013, accessed May 12, 2014, http://www.earth-policy.org/data_center/C24. [these numbers taken from an excel document associated with the Earth Policy Institute, as background for Lester Brown book.]
[verified 4/15/14]