Together with the environmental evaluation of the given production practices on the farms a site specific index of goal attainment (IGA) can be calculated for all single fields on all farms. The picture shows how the farmer chosen production practices contribute to the reduction of nitrate losses on site. The goal is thus the reduction of nitrate losses to ground and surface waters. The index of goal achievement ranges between 0 (= totally of mark) and 1 (= goal is met completely).
In this case this refers to all nitrate is lost or no nitrate is lost at all, respectively.