What is the fine-grained topic of the following text: Having observed DE’s superior performance with its ability to reduce the number of weevils by up to 98 percent uniformly across all three storage methods (traditional woven sack, hermetic bag, and hermetic drum), we were interested to compare the economic returns of these options and determine which method offered the best return on investment. Only return the topic.
Comparing the economic returns of weevil reduction methods in storage options.