Normalized Data

Coparing census demographics from different census years can be a difficult task due to changing geographic boundaries. Our normalized data product line assists researchers with comparisons of data across time by adjusting and weighting the census data to account for changes in geographies.

To demonstrate some of the issues associated with changing boundaries, below is a comparison of Pima County, Arizona in 1990 and 2000 at the Census Tract level. During this time span, Pima County expanded in population. A quick appraisal of the two maps below demonstrates the numerous changes that occurred in the census tract boundaries, specifically the addition of 83 tracts in 2000.

Pima County, AZ
Total Census Tracts (115)
Pima County, AZ
Total Census Tracts (198)

Discounted Demographic Data Packages with Normalized Data. We also have Demographic Data Packages that include both combinations of normalized and non-normalized datasets:

  • Time Series Research Package. This package is our most complete package with normalized and un-normalized census data from 1970, 1980, 1990, 2000, 2010 and now 2020. If you need instant access to all the data, this is the best discounted package that covers a broad range of our demographic data product line. If you already have the 2010 package you can upgrade to the 2020 version.
  • Planners Package Plus. This combination of products was put together for planners, developers, and marketing analysts in mind. It covers multiple decades – with the 2000 and 2010 data normalized to the 2020 boundaries, and the 2020 Census data, as well as the current year population estimates and 5-year population projections also in the 2020 boundaries