Growth rates of fertilizer, pesticide, and seed costs have been higher in years following 2006 than they were between 1990 and 2006. In 2015, the sum of fertilizer, pesticide, and seed costs were 48% of crop revenue, much higher than the 36% average from 1990 to 2006. These costs need to decrease, particularly if corn prices remain below $4.00. Otherwise, it will be difficult for revenues to be less than total costs.
For more on this topic, including graphs and data, please visit http://farmdocdaily.illinois.edu/2016/07/growth-rates-of-fertilizer-pesticide-seed-costs.html
Source: Gary Schnitkey and Sarah Sellars, University of Illinois