These are the six zoning systems which we have used for the analysis. We have divided these into an

urban core;
outer urban ring; and
a hinterland or periphery

They are very different in terms of scale with the following areas in sq kms and populations in '000's:

Bristol - area = 1346 pop (1991) = 932
Brussels - area = 4331 pop (2001) = 2944
Helsinki - area = 15135 pop (1999) = 1541
Milan - area = 1966 pop (2001) = 3606
Rennes - area = 2550 pop (1999() = 521
Stuttgart - area = 3653 pop (2000) = 2613