Updating Ravenstein: Internal Migration as a Driver of Regional Population Change in the Wider South East of England

Abstract

Key among Ravenstein's "laws", derived from extensive analysis of mid-19th century migration patterns in the British Isles, are that the majority of migrants go only a short distance and that migration proceeds stepwise as a sequence of localised population shifts towards the principal centres of commerce and industry. This paper tests these two laws in the 21st century context of counterurbanisation by reference to migration taking place within the Wider South East (WSE) of England, being the region dominated by deconcentration pressures emanating from London. It comprises two sets of empirical analyses using migration data for the period 2001-2016. Firstly, these data are aggregated to a set of broadly concentric rings around this core and analysed to reveal how much of the net outward shifts of population produced by this migration arises from net movement taking place between adjacent rings as a type of cascade as opposed to leapfrogging directly from the core into a non-adjacent ring. Cascading is found to predominate at this scale, confirming the continued importance of shorter-distance moving. Secondly, the migration data are rendered into a Travel to Work Area (TTWA) framework to examine the extent to which these subdivisions of the WSE perform a type of entrepôt role in helping to shift population outwards from London. Drawing on Ravenstein’s concepts of counties of "transfer" and "absorption", two measures are developed for revealing how the net inflow to a particular TTWA from rings closer to the core compares numerically with the net outflow from that TTWA to the rings further away from it. The derived transfer and absorption rates are then used to classify the TTWAs into four groups according to whether their scores on each are above or below average. It is found that a TTWA's role varies according to two main dimensions: the concentric zone to which it belongs and the radial sector out of London in which it is located, notably whether the sector has a coastal or landward border.