Table 1 Estimated impact of GE varieties on pesticide use, average impact over 1998–2011 (assumes βt = β, ∀ t).

N = number of observations. SEs (in parentheses) are clustered at the farmer level. The model includes time fixed effects, CRD-specific time trends, and individual (farmer) fixed effects. *P < 0.05, **P < 0.01, ***P < 0.001. a.i., active ingredient.

Soybean herbicidesMaize herbicidesMaize insecticides
a.i. kg/haEIQ kg/haa.i. kg/haEIQ kg/haa.i. kg/haEIQ kg/ha