The data used in this study is collected under BERAS Implementation project from ERA-farms in Finland in 2010 to 2012 (three years averages) and from three different production lines on ERA farms: beef, egg and milk.The data indicates the production level, the products sold and feed and other supplements purchased on the farm each year. Accordingly it has been calculated A) how much area B) how much other inputs (e.g. nitrogen and phosphorus) is needed to maintain the production level. Based on these calculations it makes possible to estimate how much of these nutrients are recycledon the farm, how much of the used nitrogen is based on biological nitrogen fixation and how much non-renewable resources have been needed. This makes it possible to calculate the output-input ratio of nitrogen
