The OECD regional typology takes into account geographical differences and enables meaningful comparisons between regions belonging to the same type. Regions are classified as: predominantly rural, intermediate, or predominantly urban, based on the percentage of population living in local rural units. This typology has been refined by introducing a distance criterion, measured in the driving time to the nearest large urban centre. Thus, a predominantly rural region will be classified as a "predominantly rural remote region" if a certain percentage of its population needs more than a fixed time to reach the nearest large urban centre; otherwise, the rural region is classified as "predominantly rural close to a city". This extended typology has been applied to North America, Europe and Japan.