Greenhouse gas emissions

The reporting_entity field shows that about 15% of rows have changed their entity code between the first and second half of the year, which is unusual. If the same location can report under different codes, that creates a matching problem in the time series. Should we standardize the entity codes, or should we note the instability?

The Montréal methodology description references a technical note that doesn't appear to exist in the dataset — it's cited but not attached. Without the note, it's impossible to assess whether the 1998 baseline is comparable to later years. Should we reconstruct the note from the source, or should we add a caveat that the early Montréal data is of unknown comparability?