@article{Yu:54147,
      recid = {54147},
      author = {Yu, Tian and Babcock, Bruce A.},
      title = {Are U.S. Corn and Soybeans Becoming More Drought  Tolerant?},
      address = {2009-10},
      number = {1040-2016-85200},
      series = {CARD Working Paper},
      pages = {42},
      year = {2009},
      abstract = {An objective drought index that measures the dry and hot  conditions adversely affecting crop yields is used in a  regression analysis to test whether corn and soybeans have  become more drought tolerant. Results indicate that corn  yield losses, whether measured in quantity terms or as a  percentage of mean yield, have decreased. The null  hypothesis that the absolute level of soybean yield losses  due to drought has not changed cannot be rejected. But  yield losses in percentage terms have decreased over time.  Because drought is the primary cause of yield loss in the  U.S. crop insurance program and because U.S. crop insurance  rates assume that percentage of yield losses are constant  over time, these results indicate that U.S. crop insurance  rates in the Corn Belt are too high.},
      url = {http://ageconsearch.umn.edu/record/54147},
      doi = {https://doi.org/10.22004/ag.econ.54147},
}