Addressing anomalies in the 2001 Census

When the 2001 Census Results were published a number of local authorities, but most notably Manchester and Westminster, saw dramatic drops in their respective population estimates, which did not accord with the authorities’ perception of the demand for their services. The 2001 Census was based on a robust methodology specifically designed to eliminate some of the undercount problems that had occurred in 1991, so ONS were confident in their results.

Manchester City Council, which was about to sponsor a third round of JUG-T, approached MGL to see if we could assist in confirming the evidence that they believed demonstrated a 2001 undercount. However much of their internal evidence was contradictory, making it difficult to persuade ONS that it was valid. ONS agreed, not only, to take into account an audit of Manchester’s data carried out by MGL, but also to employ MGL to assist in an internal re-appraisal of the census results for Manchester.

ONS employed a team of leading experts to act as a peer review panel for the MGL work, which was approved and provided the basis for the settlement of the disagreement over Manchester’s population which was re-estimated as being 27,000 higher than the Census had shown, which in turn has increased the City’s share of Revenue Support Grant by some £10 m per annum.