2. Screening for the absolute values of certain proxy approaches, and then checking the flow-specific documentation of the ecoinvent datasets or the original data sources to confirm proxy-data use. 100 3. Screening for the specific heat-to-electricity ratio of the proxy data (as the unallocated ecoinvent datasets were unavailable to us, and the allocation procedure changes the absolute numbers but leaves the ratio of inputs unchanged), and again confirming with the documentation. 105 4. Manually analyzing the documentation of cases with suspected proxy use in ecoinvent datasets (for example where input values were very close but not identical to the proxy approach values).