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Approach to Monitoring the SDGs: https://ec.europa.eu/eurostat/documents/3217494/9237449/KS-01-18-656-EN-N.pdf/2b2a096b-3bd6-4939-8ef3-11cfc14b9329.
Of note: EU approach to passenger volumes:
Passenger volumes
"This indicator meameasures the share of buses, including coaches and trolley-buses, and trains in total passenger transport performance, expressed in passenger-kilometres (pkm). Total passenger transport here includes transport by passenger cars, buses and coaches, and trains, and excludes air and sea transport. All data should be based on movements within national territories, regardless of the nationality of the vehicle. The data collection is voluntary and not fully harmonised at the EU level. Other collective transport modes, such as tram and metro systems,
are not included due to the lack of harmonised data."
Freight volumes
"This indicator measures the share of rail and inland waterways in total inland freight transport, expressed in tonne-kilometres (tkm). Inland freight transport modes include road, rail and inland waterways. Rail and inland waterways transport is based on movements on national territory, regardless of the nationality of the train or vessel. Road transport is based on all movements of vehicles registered in the reporting country. The redistribution of road transport according to the ‘territoriality principle’ involves modelling the likely journey itinerary and projecting it on to the European road network. Neither sea nor air freight transport are represented in the indicator.
Additional Indicators
Average CO2 emissions per km from new passenger cars.
and to freight volumes 
.
United Nations Conference on Trade and Development
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