Rural municipalities are scarcely populated and have little human activities (living, working, going to school, shopping, going out, recreation, etc.). These activities are expressed in the so-called OAD. The OAD is defined as the average number of addresses per km² in a circular area with a radius of one kilometre for each address. The OAD of a municipality is the average value of all OADs of all addresses within that municipality and determines the degree of urbanisation. The following categories are distinguished in this article:
Urbanised municipalities, including more than 1,000 addresses per km².
Rural municipalities, including fewer than 1,000 addresses per km².