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Sex ratio patterns in population estimates.

Steve Smallwood¹, Sofie De Broe

¹Office for National Statistics.

Population Trends

|October 20, 2009

Summary

This summary is machine-generated.

Mid-year estimates (MYEs) in England and Wales show an unusual sex ratio pattern post-2001 Census. This research investigates the drivers of this demographic shift and offers insights for future census preparations.

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Area of Science:

Demography
Population Statistics
Census Methodology

Background:

The 2001 Census in England and Wales revealed a distinct sex ratio pattern in mid-year estimates (MYEs) compared to previous periods.
Understanding demographic shifts is crucial for accurate population projections and policy-making.

Purpose of the Study:

To explain the observed sex ratio pattern in England and Wales (EW) following the 2001 Census.
To propose strategies for improving census and population estimation methods for 2011 and beyond.

Main Methods:

Comparative analysis of sex ratios using Patient Register Data (PRD) and international comparisons.
Investigated demographic trends in migrant populations (EW and foreign-born).
Performed accounting exercises for unexplained discrepancies between estimates and census data.

Main Results:

Identified specific demographic factors contributing to the altered sex ratio patterns in MYEs.
Highlighted the influence of migration on the overall sex ratio.
Provided evidence-based explanations for the divergence observed post-2001.

Conclusions:

The study elucidates the complex factors influencing sex ratio patterns in population estimates.
Recommendations are provided for enhancing the accuracy and reliability of future census data and MYEs.