There are two categories of factors in SERAM:

• Generic factors, such as an efficiency factor, or a currency conversion, which is applied to inputs independently of the methodology used.
• Method factors which are specific to the methdology, such as tCO2e/GWh for computing the emissions of electricity consumption in the GHG method.

The method factors are therefore defined on the method and not related to a specific reporting period. Also, they behave differently from plain Factor Indicators in that themost specific factor is always used. For instance, there are world-wide averages known for emissions from grid electricity, but some countries have more specific known factors and maybe there is a even more specific provider-dependent factor available.

Method Factors are managed as list where each entry defines the different partial factor values for an indicator, structure and date from when on that factor is valid. Comments and units can also be specified per factor entry.