Currently, they are produced on a sectoral level based on firm-level surveys on input structure and carbon emissions. 16 Von Kalckreuth (2022a) studies this process and shows how it can converge. Market learning is simulated based on data for Germany.
17 See WRI and WBCSD (2004) on direct emissions, and WRI and WBCSD (2011a) on indirect emissions, as well as WRI and WBCSD (2011b) for measurement at the product level. Regarding indirect emissions, the GHG Protocol has been criticised for its optionality and the impracticality of measurement it measurement suggestions. Firms are supposed to collect their own information on their respective value chain.