The Residential Mobility and Deprivation (RMD) data provide yearly Local Authority District (LAD) level estimates of the mean differences of residential mobility and deprivation of all known adults’ moves to, from and within each neighbourhood (LSOA11CD and equivalent) in the UK for 1997-2023.

Methodology

The data are created from multiple data sources, which are blends of English Index of Multiple Deprivation (EIMD), Welsh Index of Multiple Deprivation (WIMD), Scottish Index of Multiple Deprivation (SIMD), Northern Ireland Multiple Deprivation Measure (NIMDM), and CDRC Secure data Linked Consumer Registers.

Indices of Multiple Deprivation (IMDs) are summary measures of physical and social conditions compiled by statistical authorities for neighbourhood areas across the country for each Lower layer Super Output Area (LSOA: England and Wales), Data Zone (DZ: Scotland) and Super Output Area (SOA: Northern Ireland). Area ranks within each UK country were standardised into percentile scores, with low values denoting more deprived LSOAs.

These scores from each national IMD were ranked and interleaved with the most contemporaneous ranked scores for the other UK countries. The resulting sequence was then ranked as a UK index of percentile scores. The most deprived area has the lowest rank (1), and the least deprived area has the highest rank (100).

Three ‘Harmonised’ IMD datasets were assembled for circa 2004 (2004 EIMD, 2005 WIMD, 2004 SIMD and 2004 NIMDM), 2010 (2010 EIMD, 2011 WIMD, 2012 SIMD and 2010 NIMDM) and 2019 (2019 EIMD, 2019 WIMD, 2020 SIMD and 2017 NIMDM).

CDRC Linked Consumer Registers (LCRs) are based upon annual updates of the names and addresses for adult UK residents from 1997 onwards. They offer a near-complete coverage of the adult population at individual level (Lansley et al 2019; van Dijk et al 2021). ‘Harmonised’ IMD ranks for 2004, 2010 or 2019 were assigned to LCR name and address records for proximal years (2004 values assigned to 1997-2007, 2010 values assigned to 2008-2014 and 2019 values assigned to 2015-2020) to cover the entire period of the LCRs.

The RMD Indexes were then created by subtracting the percentile score of each LCR mover’s origin neighbourhood from that of their destination, with positive values indicating moves to less deprived neighbourhoods. Mean differences between these values were calculated for (a) movers to each different destination neighbourhood, (b) moves from each different origin neighbourhood and (c) moves within the same neighbourhood.

These data allow researchers to whether incoming residents likely originate from more or less deprived neighbourhoods, perhaps indicating neighbourhood gentrification or relative obsolescence, each over an extended period. The annual estimates and attribution of precise neighbourhood origins and destinations extends what is available from decennial census data. In addition, researchers can investigate which neighbourhoods are platforms for moves to less or more deprived neighbourhoods, indicating neighbourhood roles in facilitating social mobility. LCR estimates are triangulated with census statistics and can be used to update them during intercensal periods.

Note: Any '*' in the index means that the figures were suppressed to avoid disclosive issues (i.e., lower count). RMD figures are measured at a percentile scale.

For detailed description of the columns contained within the data, see the Variable Dictionary; and for an overview of the characteristics of the data, see the Data Summary. These files can be downloaded from the bottom of this page.

Quality, Representation and Bias

The underpinning data are the Linked Consumer Registers (LCRs), the provenance of which is set out in two papers linked below. Please see these papers for additional details about the data.

Consumer and administrative data were acquired directly or indirectly from multiple data providers without warranties about accuracy or coverage, consistent with industry practice. Extensive internal and external validation procedures were developed in order to render the diverse data formats consistent and to establish the provenance of the consolidated registers. Known shortcomings in the data and over-all assessment of quality are set out in the peer-reviewed research papers.

In addition to establishing consistency of address referencing, the research papers document the completeness of the data. In terms of coverage, the LCRs tend to under-estimate LSOA adult population sizes relative to UK mid-year population estimates for 2003-2020. The research papers describe procedures developed by the CDRC to fill in known gaps where possible.

Data for Northern Ireland are estimated to be less complete because of specific administrative procedures and legislative requirements. Additional UK-wide issues are created by second-home owners and students.

The other underpinning data (i.e., IMDs) are from each country of the UK. These datasets address the same general concept and use the same approach, although there is variability in precise domains, weighting and geographies. To make them as comparable and consistent as possible, percentile score and 2020 UK LSOA geographies (identical to 2011 UK LSOA geographies) were used to harmonise results.

Whilst collaborating value added data resellers have attempted to compile address lists that have full and accurate coverage, the research papers identify systematic biases akin to those found in similar data sources. The primary data source over the period is the public version of UK Electoral Registers, the coverage of which has been in decline since the advent of opt out provisions in 2002. Post 2002 LCRs are understood to under-represent adults drawn from ethnic minorities and those resident in rented accommodation.

CDRC research using a names-based tool to infer ethnicity, developed in collaboration with the Office for National Statistics (ONS) has quantified the slight over-representation of White British adults. Approximately 84% of LCR individuals were classed as White British, compared to 81% self-identifying as such in the 2011 UK Census. Research also identified that areas with higher proportion of adults in rented accommodation had the greatest under-representation within cities.

The counts of individuals in the original LCR data fluctuate according to data supplier in addition to actual population size changes. As such, meta data describing the annual distribution of population counts across LAD that have been used in calculating RMD are made available. RMD may be out of line with census counts and users should consult census statistics if they have concerns.