Estimating components of population change from census data for incongruent spatial/temporal units and attributes

When calculating the components of population change over time, the spatial units of analysis must remain constant. However, the boundaries of these units often change from one census to the next Another limiting factor is the absence of data values for the time period. Net migration figures might be available for a five year interval in a census but not for a twenty year interval. GIS and areal interpolation are used here to rectify boundary changes that occur from one census to the next and shift-share analysis is used to estimate the components of population change from the census data. These methods are applied to a county level study of population change in China between 1982 and 2000.