US farmers producing more corn with less fertilizer

From 1980 to 2010, U.S. farmers reduced their fertilizer use by 4% while nearly doubling corn production.

U.S. farmers increased corn production by 87.5% using 4% fewer fertilizer nutrients from 1980 to 2010, according to The Fertilizer Institute. 
In 1980, farmers grew 6.64 billion bushels of corn using 3.9 pounds of nutrients — nitrogen, phosphorus and potassium — for each bushel, and in 2010 they grew 12.45 billion bushels using 1.6 pounds of nutrients per bushel produced.
“Through improvements in modern technology and old-fashioned ingenuity, our farmers are using fertilizer with the greatest efficiency in history and have again shown why U.S. agriculture will continue to feed the world,” said TFI President Ford West. “Fertilizer nutrients are essential components in food, feed, fiber and fuel production and we anticipate that maximizing production from future new seed varieties will require a diet that can only be met through the efficient use of commercially produced fertilizers.”
The continued growth of such efficiencies, said West, is playing a role in agriculture's environmental stewardship as well as promoting efficient food production. "We think this is a triumph of the role science and economics play in sustainable farming," said West. "We expect that through the more widespread adoption of 4R nutrient stewardship (use of the right fertilizer source at the right rate, right time and right place), farmers and the fertilizer industry will continue to help feed a growing world population.”