The estimates are derived from the LFS from the period January to March 2018, and are not seasonally adjusted.
The sample used for this data is made up of approximately 40,000 UK households and 100,000 individuals per quarter. The sampling frame used is the Postcode Address File and NHS communal accommodation.
The Labour Force Survey uses calibration weighting. Weighting is used to adjust the results of a survey to make them representative of the population and improve their accuracy.
For example, a survey which contains 25% women and 75% men will not accurately reflect the views of the general population, which we know has an even 50/50 split.
Statisticians rebalance or ‘weight’ the survey results to more accurately represent the general population. This helps to make them more reliable.
Survey weights are usually applied to make sure the survey sample has broadly the same gender, age, ethnic and geographic make up as the general population. The weights here are formed using a population weighting procedure which involves weighting data to sub-regional population estimates and then adjusting for the estimated age and sex composition by region.
Estimation to population totals and projections are based on the 2011 Census.
Suppression rules and disclosure control
Data was suppressed in groups with small sample sizes, because it is not possible to produce robust estimates with small sample sizes.
For example, in the 75+ age group in the Other including Mixed ethnic group, the sample size was only 22, which is too small to produce a reliable estimate. The results for this age group were therefore suppressed.
Statistical disclosure control methodology is applied to the Labour Force Survey data (the source for this data). This ensures that information attributable to an individual is not disclosed in any publication, and that confidentiality of respondents is protected in data sets.
As an example, the results for the 65 to 74 group in the Other including Mixed ethnic group were suppressed (it had a fairly small sample of 59). This was done to ensure that the results for the 75+ group in the Other including Mixed ethnic group could not be worked out by deduction.
The Code of Practice for Official Statistics, and specifically Principle 5, Confidentiality, sets out the principles for protecting data from being disclosed. The Statistics and Registration Service Act 2007 includes data confidentiality regulations which apply to Office of National Statistics (ONS). More information about disclosure control on data tables and data sets is available on the ONS website.
We round numbers, and for this reason some figures may not add up.
Related publicationsQuality and methodology information
Further technical information
Further quality and methodology information, user guides and example questionnaires can be accessed on the ONS website