(81) Co-products from the production and use of fuels should be taken into account in the calculation of greenhouse gas emissions. The substitution method is appropriate for the purposes of policy analysis, but not for the regulation of individual economic operators and individual consign- ments of transport fuels. In those cases the energy alloca- tion method is the most appropriate method, as it is easy to apply, is predictable over time, minimises counter- productive incentives and produces results that are gener- ally comparable with those produced by the substitution method. For the purposes of policy analysis the Commis- sion should also, in its reporting, present results using the substitution method. (82) In order to avoid a disproportionate administrative burden, a list of default values should be laid down for common biofuel production pathways and that list should be updated and expanded when further reliable data is avail- able. Economic operators should always be entitled to claim the level of greenhouse gas emission saving for bio- fuels and bioliquids established by that list. Where the default value for greenhouse gas emission saving from a production pathway lies below the required minimum level of greenhouse gas emission saving, producers wish- ing to demonstrate their compliance with this minimum level should be required to show that actual emissions from their production process are lower than those that were assumed in the calculation of the default values. (83) It is appropriate for the data used in the calculation of the default values to be obtained from independent, scientifi- cally expert sources and to be updated as appropriate as those sources progress their work. The Commission should encourage those sources to address, when they update their work, emissions from cultivation, the effect of regional and climatological conditions, the effects of cultivation using sustainable agricultural and organic farming methods, and the scientific contribution of producers, within the Com- munity and in third countries, and civil society.