Figure 4.

The number of studies on pest control detected in 2015/16 as a function of (a) insecticide usage in kg/ha derived from ECPA and USDA data from 2003; (b) the most recent yield data from the FAO in kg/ha from 2014. Predicted values of the negative binomial generalized linear model are shown (Model 1, blue lines; 95% confidence intervals are shown in grey). The category ‘other vegetables’ at 3.9 kg/ha of insecticides in 2003 (10 pest control studies published; yield estimated at 15.9 t/ha in 2014) was excluded from the model as an outlier for insecticides (see Methods).