The researchers compared different methods for calculating evapotranspiration in New Delhi, India. They found that the Penman–Monteith ASCE and FAO 56 Penman–Monteith models performed slightly better than other models under water stress conditions. The study used data from maize harvest seasons between 1976 and 2006 to evaluate the models, considering factors like crop coefficients and meteorological parameters. The results showed that these two models were more accurate in predicting evapotranspiration in the given conditions.