For example, it could provide the necessary data to calculate the required increase in imported food as a result of an increase in biofuels production (and the resulting substitution of food crops). Similarly, with the exception potentially of major policies, ECA cannot really serve to monitor, with any accuracy, the impacts of a specific policy over time - causal chains and proven correlations would be needed and will be very difficult, if not impossible, to establish. It may well be, however, that other tools are just as good as the ECA for doing this, especially at the local level, where further information and data could possibly feed into an analytical framework/tool.