Price quote data (for locally collected data only) and consumption segment indices that underpin consumer price inflation statistics, giving users access to the detailed data that are used in the construction of the UK’s inflation figures. The data are being made available for research purposes only and are not an accredited official statistic. From October 2024, private school fees and part-time education classes have been included in the consumption segment indices file. For more information on the introduction of consumption segments, please see the Consumer Prices Indices Technical Manual, 2019. Note that this dataset was previously called the consumer price inflation item indices and price quotes dataset.

Tables showing comparability of Census 2021 microdata samples with Census 2021. Category proportions for selected univariate and multivariate datasets from the microdata sample and the Census 2021 have been compared.

Abstract copyright UK Data Service and data collection copyright owner.

The UK censuses took place on 27 March 2011. They were run by the Northern Ireland Statistics & Research Agency (NISRA), National Records of Scotland (NRS), and the Office for National Statistics (ONS) for both England and Wales. The UK comprises the countries of England, Wales, Scotland and Northern Ireland.

Statistics from the UK censuses help paint a picture of the nation and how we live. They provide a detailed snapshot of the population and its characteristics and underpin funding allocation to provide public services. This is the home for all UK census data.

Abstract copyright UK Data Service and data collection copyright owner.

The 2021 UK Census was the 23rd official census of the United Kingdom. The UK Census is generally conducted once every 10 years, and the 2021 censuses of England, Wales, and Northern Ireland took place on 21 March 2021. In Scotland, the decision was made to move the census to March 2022 because of the impact of the coronavirus pandemic. The censuses were administered by the Office for National Statistics (ONS), the Northern Ireland Statistics and Research Agency (NISRA) and National Records of Scotland (NRS), respectively. In England and Wales, Census 2021 was the first census with a digital-first design, encouraging participants to respond online rather than on a paper questionnaire.

Topics covered in the 2021 UK Census included:

• demography and migration
• ethnic group, national identity, language and religion
• labour market and travel to work
• housing
• education
• health, disability, and unpaid care
• Welsh and other languages
• UK armed forces veterans
• sexual orientation and gender identity.

The 2021 Census: Safeguarded Individual Microdata Sample at Grouped Local Authority Level dataset consists of a random sample of 5% of person records from the 2021 Census. It includes records for 3,021,611 persons. These data cover England and Wales only. The lowest level of geography is grouped local authority. This means groups of local authorities or single local authorities where the population reaches at least 120,000 persons. The dataset contains 87 variables and a low level of detail.

Census Microdata

Microdata are small samples of individual records from a single census from which identifying information have been removed. They contain a range of individual and household characteristics and can be used to carry out analysis not possible from standard census outputs, such as:

• creating tables using bespoke variable combinations
• investigating specific combinations of variables or categories in a high level of detail
• conducting non-tabular statistical analyses on record-level data.

The microdata samples are designed to protect the confidentiality of individuals and households. This is done by applying access controls and removing information that might directly identify a person, such as names, addresses and date of birth. Record swapping is applied to the census data used to create the microdata samples. This is a statistical disclosure control (SDC) method, which makes very small changes to the data to prevent the identification of individuals. The microdata samples use further SDC methods, such as collapsing variables and restricting detail. The samples also include records that have been edited to prevent inconsistent data and contain imputed persons, households, and data values. To protect confidentiality, imputation flags are not included in any 2021 Census microdata sample.

The 2021 Census: Safeguarded Individual Microdata Sample at Grouped Local Authority Level data cover: communal establishments, demography, education, ethnicity, identity, language, religion, health, disability, unpaid care, housing, internal migration, international migration, labour market, students, travel to work, and Welsh language.

Abstract copyright UK Data Service and data collection copyright owner.

• one public, a Teaching File of individuals (this study, SN 7613);
• two safeguarded, one file of individuals at regional level (see SN 7605) and one at local authority level (see SN 7682);
• and two secure, one file of households and one of individuals.

Table showing all variables, classifications and codes included within the Census 2021 microdata samples. This covers the secure, safeguarded and public samples.

Abstract copyright UK Data Service and data collection copyright owner.

Background

New reweighting policy
Following the new reweighting policy ONS has reviewed the latest population estimates made available during 2019 and have decided not to carry out a 2019 LFS and APS reweighting exercise. Therefore, the next reweighting exercise will take place in 2020. These will incorporate the 2019 Sub-National Population Projection data (published in May 2020) and 2019 Mid-Year Estimates (published in June 2020). It is expected that reweighted Labour Market aggregates and microdata will be published towards the end of 2020/early 2021.

Secure Access QLFS household data
Up to 2015, the LFS household datasets were produced twice a year (April-June and October-December) from the corresponding quarter's individual-level data. From January 2015 onwards, they are now produced each quarter alongside the main QLFS. The household datasets include all the usual variables found in the individual-level datasets, with the exception of those relating to income, and are intended to facilitate the analysis of the economic activity patterns of whole households. It is recommended that the existing individual-level LFS datasets continue to be used for any analysis at individual level, and that the LFS household datasets be used for analysis involving household or family-level data. For some quarters, users should note that all missing values in the data are set to one '-10' category instead of the separate '-8' and '-9' categories. For that period, the ONS introduced a new imputation process for the LFS household datasets and it was necessary to code the missing values into one new combined category ('-10'), to avoid over-complication. From the 2013 household datasets, the standard -8 and -9 missing categories have been reinstated.

Secure Access household datasets for the QLFS are available from 2002 onwards, and include additional, detailed variables not included in the standard 'End User Licence' (EUL) versions. Extra variables that typically can be found in the Secure Access versions but not in the EUL versions relate to: geography; date of birth, including day; education and training; household and family characteristics; employment; unemployment and job hunting; accidents at work and work-related health problems; nationality, national identity and country of birth; occurence of learning difficulty or disability; and benefits.

Prospective users of a Secure Access version of the QLFS will need to fulfil additional requirements, commencing with the completion of an extra application form to demonstrate to the data owners exactly why they need access to the extra, more detailed variables, in order to obtain permission to use that version. Secure Access users must also complete face-to-face training and agree to Secure Access' User Agreement (see 'Access' section below). Therefore, users are encouraged to download and inspect the EUL version of the data prior to ordering the Secure Access version.

LFS Documentation
The documentation available from the Archive to accompany LFS datasets largely consists of each volume of the User Guide including the appropriate questionnaires for the years concerned. However, LFS volumes are updated periodically by ONS, so users are advised to check the ONS LFS User Guidance pages before commencing analysis.

The study documentation presented in the Documentation section includes the most recent documentation for the LFS only, due to available space. Documentation for previous years is provided alongside the data for access and is also available upon request.

Review of imputation methods...

Central point for all MRP decisions.

Abstract copyright UK Data Service and data collection copyright owner.

The UK censuses took place on 29th April 2001. They were run by the Northern Ireland Statistics & Research Agency (NISRA), General Register Office for Scotland (GROS), and the Office for National Statistics (ONS) for both England and Wales. The UK comprises the countries of England, Wales, Scotland and Northern Ireland.

Statistics from the UK censuses help paint a picture of the nation and how we live. They provide a detailed snapshot of the population and its characteristics, and underpin funding allocation to provide public services.

Abstract copyright UK Data Service and data collection copyright owner.

Background
The Labour Force Survey (LFS) is a unique source of information using international definitions of employment and unemployment and economic inactivity, together with a wide range of related topics such as occupation, training, hours of work and personal characteristics of household members aged 16 years and over. It is used to inform social, economic and employment policy. The Annual Population Survey, also held at the UK Data Archive, is derived from the LFS.

The LFS was first conducted biennially from 1973-1983, then annually between 1984 and 1991, comprising a quarterly survey conducted throughout the year and a 'boost' survey in the spring quarter. From 1992 it moved to a quarterly cycle with a sample size approximately equivalent to that of the previous annual data. Northern Ireland was also included in the survey from December 1994. Further information on the background to the QLFS may be found in the documentation.

The UK Data Service also holds a Secure Access version of the QLFS (see below); household datasets; two-quarter and five-quarter longitudinal datasets; LFS datasets compiled for Eurostat; and some additional annual Northern Ireland datasets.

LFS Documentation
The documentation available from the Archive to accompany LFS datasets largely consists of the latest version of each user guide volume alongside the appropriate questionnaire for the year concerned (the latest questionnaire available covers July-September 2022). Volumes are updated periodically, so users are advised to check the latest documents on the ONS Labour Force Survey - User Guidance pages before commencing analysis. This is especially important for users of older QLFS studies, where information and guidance in the user guide documents may have changed over time.

LFS response to COVID-19

From April 2020 to May 2022, additional non-calendar quarter LFS microdata were made available to cover the pandemic period. The first additional microdata to be released covered February to April 2020 and the final non-calendar dataset covered March-May 2022. Publication then returned to calendar quarters only. Within the additional non-calendar COVID-19 quarters, pseudonymised variables Casenop and Hserialp may contain a significant number of missing cases (set as -9). These variables may not be available in full for the additional COVID-19 datasets until the next standard calendar quarter is produced. The income weight variable, PIWT, is not available in the non-calendar quarters, although the person weight (PWT) is included. Please consult the documentation for full details.

Occupation data for 2021 and 2022 data files

The ONS has identified an issue with the collection of some occupational data in 2021 and 2022 data files in a number of their surveys. While they estimate any impacts will be small overall, this will affect the accuracy of the breakdowns of some detailed (four-digit Standard Occupational Classification (SOC)) occupations, and data derived from them. Further information can be found in the ONS article published on 11 July 2023: Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022.

2024 Reweighting

In February 2024, reweighted person-level data from July-September 2022 onwards were released. Up to July-September 2023, only the person weight was updated (PWT23); the income weight remains at 2022 (PIWT22). The 2023 income weight (PIWT23) was included from the October-December 2023 quarter. Users are encouraged to read the ONS methodological note of 5 February, Impact of reweighting on Labour Force Survey key indicators: 2024, which includes important information on the 2024 reweighting exercise.

End User Licence and Secure Access QLFS data

Two versions of the QLFS are available from UKDS. One is available under the standard End User Licence (EUL) agreement, and the other is a Secure Access version. The EUL version includes country and Government Office Region geography, 3-digit Standard Occupational Classification (SOC) and 3-digit industry group for main, second and last job (from July-September 2015, 4-digit industry class is available for main job only).

The Secure Access version contains more detailed variables relating to:

• age: single year of age, year and month of birth, age completed full-time education and age obtained highest qualification, age of oldest dependent child and age of youngest dependent child
• family unit and household: including a number of variables concerning the number of dependent children in the family according to their ages, relationship to head of household and relationship to head of family
• nationality and country of origin
• finer detail...

Frequencies of aggregate categories of self-assigned ethnicity in 2011 Census (England and Wales) rounded to the nearest 100 from calculations made using VML.

The UK Data Service also holds a Secure Access version of the QLFS (see below); household datasets; two-quarter and five-quarter longitudinal datasets; LFS datasets compiled for Eurostat; and some additional annual Northern Ireland datasets.

LFS Documentation
The documentation available from the Archive to accompany LFS datasets largely consists of the latest version of each user guide volume alongside the appropriate questionnaire for the year concerned (the latest questionnaire available covers July-September 2022). Volumes are updated periodically, so users are advised to check the latest documents on the ONS Labour Force Survey - User Guidance pages before commencing analysis. This is especially important for users of older QLFS studies, where information and guidance in the user guide documents may have changed over time.

LFS response to COVID-19

From April 2020 to May 2022, additional non-calendar quarter LFS microdata were made available to cover the pandemic period. The first additional microdata to be released covered February to April 2020 and the final non-calendar dataset covered March-May 2022. Publication then returned to calendar quarters only. Within the additional non-calendar COVID-19 quarters, pseudonymised variables Casenop and Hserialp may contain a significant number of missing cases (set as -9). These variables may not be available in full for the additional COVID-19 datasets until the next standard calendar quarter is produced. The income weight variable, PIWT, is not available in the non-calendar quarters, although the person weight (PWT) is included. Please consult the documentation for full details.

Occupation data for 2021 and 2022 data files

The ONS has identified an issue with the collection of some occupational data in 2021 and 2022 data files in a number of their surveys. While they estimate any impacts will be small overall, this will affect the accuracy of the breakdowns of some detailed (four-digit Standard Occupational Classification (SOC)) occupations, and data derived from them. Further information can be found in the ONS article published on 11 July 2023: Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022.

2024 Reweighting

In February 2024, reweighted person-level data from July-September 2022 onwards were released. Up to July-September 2023, only the person weight was updated (PWT23); the income weight remains at 2022 (PIWT22). The 2023 income weight (PIWT23) was included from the October-December 2023 quarter. Users are encouraged to read the ONS methodological note of 5 February, Impact of reweighting on Labour Force Survey key indicators: 2024, which includes important information on the 2024 reweighting exercise.

End User Licence and Secure Access QLFS data

Two versions of the QLFS are available from UKDS. One is available under the standard End User Licence (EUL) agreement, and the other is a Secure Access version. The EUL version includes country and Government Office Region geography, 3-digit Standard Occupational Classification (SOC) and 3-digit industry group for main, second and last job (from July-September 2015, 4-digit industry class is available for main job only).

The Secure Access version contains more detailed variables relating to:

• age: single year of age, year and month of birth, age completed full-time education and age obtained highest qualification, age of oldest dependent child and age of youngest dependent child
• family unit and household: including a number of variables concerning the number of dependent children in the family according to their ages, relationship to head of household and relationship to head of family
• nationality and country of origin
• finer detail geography: including county, unitary/local authority, place of work, Nomenclature of Territorial Units for Statistics 2 (NUTS2) and NUTS3 regions, and whether lives and works in same local authority district, and other categories;
• health: including main health problem, and current and past health problems
• education and apprenticeship: including numbers and subjects of various qualifications and variables concerning apprenticeships
• industry: including industry, industry class and industry group for main, second and last job, and industry made redundant from
• occupation: including 5-digit industry subclass and 4-digit SOC for main, second and last job and job made redundant from
• system variables: including week number when interview took place and number of households at address
• other additional detailed variables may also be included.

The Secure Access datasets (SNs 6727 and 7674) have more restrictive access conditions than those made available under the standard EUL. Prospective users will need to gain ONS Accredited Researcher status, complete an extra application form and demonstrate to the data owners exactly why they need access to the additional variables. Users are strongly advised to first obtain the standard EUL version of the data to see if they are sufficient for their research requirements.

Latest edition information

For the second edition (January 2025), the 2018 person weight (PWT18) was replaced with the 2024 person weight (PWT24). Only the person weight has been replaced with a 2024 version; the 2018 income weight (PIWT18) remains.

Percentage of total wealth owned by households in each decile for London and Great Britain. Data extracted from the ONS Wealth and Assets Survey (WAS) microdata. This dataset is one of the Greater London Authority's measures of Economic Fairness. Click here to find out more.

First set of follow-up algorithms and their main characteristics.

A 1% sample of individual records from Census 2021 with no identifying information and available to all for teaching of statistics and social sciences.

The data are based on the 2011 Census Microdata Teaching File, with the first 18 variables exactly the same as those found in the original file, which can be downloaded from: http://www.scotlandscensus.gov.uk/microdataThe final 10 variables found in the file, highlighted in yellow, are synthetic data. Those variables corresponding to a 2001 state are based on the transitional probabilities taken from the ONS longitudinal study, accurate to 10 year age groups.Details of the synthetic variables can be found in the Synthetic Variables sheet in this file. Details of the original variables can be found in the meta data accompanying the original microdata teaching file.

Abstract copyright UK Data Service and data collection copyright owner.The UK censuses took place on 29th April 2001. They were run by the Northern Ireland Statistics & Research Agency (NISRA), General Register Office for Scotland (GROS), and the Office for National Statistics (ONS) for both England and Wales. The UK comprises the countries of England, Wales, Scotland and Northern Ireland.Statistics from the UK censuses help paint a picture of the nation and how we live. They provide a detailed snapshot of the population and its characteristics, and underpin funding allocation to provide public services. The Census 2001: Small Area Microdata SAM is a 5% sample of individuals for all countries of the UK, with 2.96 million cases. Local Authority is the lowest level of geography for England and Wales, Council Areas for Scotland and Parliamentary Constituencies for Northern Ireland. The Scilly Isles have been merged with Penwith and the City of London with Westminster. Orkney and Shetland are merged into one area. All other areas are identified. The median sample size for an authority is 5,600 records and nearly eighty authorities have more than 10,000 records. The amount of individual detail in the SAM is less than in the 2001 Individual Licenced Sample of Anonymised Records (I-SAR)(see under SNs 7205 and 7206) because of the greater geographical detail in the SAM. Caveat - Students: As with the Individual SAR, the SAM includes those enumerated in a communal establishment and also full-time students who were enumerated at an address that was not their usual term-time residence. For the latter there is only individual-level information on age, sex, marital status and full-time student status. It is recommended that these students are not included in any analyses as they do not form part of the usual residents population base. This dataset contains 88 variables; a version designed for imputation analysis, which contains an extra 67 imputation flag variables, is available under SN 7208. Main Topics:Accommodation type (brief)Accommodation type (detailed)Adults, Number Employed in HouseholdAdults, Number in HouseholdAgeAge of Family Reference Person (FRP)Age of Household Reference Person (HRP)Age of Students and SchoolchildrenAmenitiesArmed ForcesBath/Shower and Toilet, use ofCare (unpaid), Provision ofCare, Provision ofCarers and their Economic Activity, Number ofCars and vansCentral heatingChildrenChildren, dependentCommunal Establishment ResidentsCommunal establishment, combined type and managementConcealed familiesCountry of birthCountry of Birth (additional categories)Daytime PopulationDwelling TypeEconomic ActivityEconomic Activity of Associated People Resident in HouseholdsEconomic Activity of Full-time studentsEconomic Activity of Household Reference Person (HRP)Ethnic group (England and Wales)Ethnic group (England and Wales) of Household Reference PersonFamily compositionFamily statusFamily typeHealth, GeneralHours workedHousehold compositionHousehold composition (alternative classification)Household dependent childrenHousehold deprivationHousehold Reference Person indicatorHousehold sizeHousehold Space TypeHousehold TypeHouseholds with students away during term-timeIndustryIndustry, formerLimiting long-term illnessLimiting Long-Term Illness (LLTI), Household residents withLimiting long-Term Illness, number of people with in householdLiving arrangementsLiving arrangements of Household Reference Person (HRP)Lowest floor levelMarital statusMigration (armed forces)Migration (Communal establishment)Migration (People)Multiple ethnic identifierOccupancy RatingOccupation (brief)Occupation (detailed)Occupation, formerPensioner householdPeople aged 17 or over in household, Number ofPopulation TypePublic transport users in householdsQualifications (England and Wales)Qualifications, highest level of (England and Wales)Qualifications, professionalReligion (England and Wales)Religion (England and Wales) of Household Reference PersonResident BasisResident TypeRooms in a dwelling, number ofRooms, Number ofRooms, Persons perSexSex of Household Reference Person (HRP)Single Adult HouseholdsSocial Grade of Household Reference Person (HRP), approximatedSocial Grade, approximatedSocio-economic Classification (NS-SeC)Socio-economic Classification (NS-SeC) of Household Reference Person (HRP)Socio-economic Classification (NS-SeC) of Household Reference Person (HRP), Main categories ofStudent accommodation (Standard Output)Student accommodation TypeStudent statusTenureTenure, dwellingTime Since Last WorkedTravel to Work, distanceTravel to work, Means ofTravel to Work, Method of and Number of Employed PeopleWorking ParentsYear last worked

The Census-based surname lookup table for Ethnicity Estimator.

Example of assigning ethnic class using Ethnicity Estimator.

A list of the data sources used to compile the supply and use tables. This also includes how this data is sourced, the area of National Accounts that use it and the transaction it feeds into.