Embrapa?s PECUS project aims to estimate greenhouse gas emissions (GGE) and recommend technological solutions for reducing CO2-e emission intensity from beef cattle production systems. PECUS project identified 23 typical production systems that represent most of the Brazilian beef cattle production and defined mathematical models for their technical and economic performance and CO2-e emission intensity. Choosing the right performance indexes can help to compare different production systems and identify opportunities for improvement. This work describes a way of splitting emission intensity from enteric fermentation and manure decomposition of a beef cattle production system as a product of performance ratios inspired by Du- Pont identity used for financial performance analysis (MATT, 2016). Selected production systems identified by the PECUS project were compared through these performance ratios in order to evaluate if they can help on identifying opportunities for the reduction of CO2-e emission intensity