U.S. Corn Yields Have Increased Six Times Since the 1930s and Are Estimated to Double By 2030. Mark Perry

The chart above displays annual U.S. corn yields (bushels per acre) back to 1866 (USDA data here).  After remaining flat between 1866 and 1939 at about 26 bushels per acre, corn yields started increasing dramatically in the 1940s due to the introduction of hybrid seeds, and the widespread use of nitrogen fertilizers and herbicides (source).  By 2009, average corn yields had increased by more than six times to a record high 165 bushels per acre, before falling to 153 bushels per acre last year, and an estimated 148.1 bushels per acre for 2011.    

Corn facts from the Corn Farmers Coalition:

1. Farmers today grow five times as much corn as they did in the 1930s – on 20 percent less land. That is 13 million acres or 20,000 square miles, twice the size of Massachusetts. The yield per acre has skyrocketed from 24 bushels in 1931 to 154 now, or a six-fold gain. 

2. The national average of 153 bushels produced on each acre in 2010 was nearly 20 percent larger than the average yield in 2002 – and plant breeding experts estimate yields may jump 40 percent before 2020 and, perhaps, hit a national average of 300 bushels per acre by 2030.

3. America’s corn farmers are by far the most productive in theworld, growing 20% more corn per acre than any other nation.

From Mark Perry blog.