The estimates refer to the population as at 30 June each year. The population estimates and Scotland and council levels are published ten months after this data. The small area population estimates are published fourteen months after this date. Mid-year population estimates at Scotland and council level, and Health Board areas are published by NRS in April every year. Small area population estimates at data zone and intermediate zone levels, Scottish Parliamentary Constituency and UK Parliamentary Constituency, are published by NRS in August every year. The dates of publications are preannounced on the [Future Publications]( https://www.nrscotland.gov.uk/statistics-and-data/future-publications) section of the NRS website.
Population estimates are used for a variety of purposes including resource allocation and planning of services such as education and health. They are also used for calculating rates and performance measures, informing local and national policy, weighting surveys and in modelling the economy. In addition, population estimates at data zone level can be used as building blocks for a variety of different geographies that can inform planning, provision of services at sub-council area level and allocation of resources. They are used as the denominator to calculate many per capita rates and are available to use as the denominator in devising other rates a user might wish to create. The estimates are also important in a number of other applications, such as the development and maintenance of the Scottish Government's Urban Rural Classification and the Scottish Index of Multiple Deprivation (SIMD).
Population estimates are based on the 2001 Census and updated annually by 'ageing on' the population and applying information on births, deaths and migration.
*Coherence* - Further information on the population estimates can be found in methodology sections on the National Records of Scotland (NRS) website for [Mid-year Population Estimates]( https://www.nrscotland.gov.uk/statistics-and-data/statistics/statistics-by-theme/population/population-estimates/mid-year-population-estimates) and [Small Area Population Estimates](https://www.nrscotland.gov.uk/statistics-and-data/statistics/statistics-by-theme/population/population-estimates/special-area-population-estimates/small-area-population-estimates). *Comparability* - The statistics are designed to be consistent, and incorporate comparable historical data where appropriate. The small area estimates are consistent with the higher level mid-year estimates for council areas and for Scotland. PLEASE NOTE: The data zone aggregations for council areas, health boards and total Scotland for years 2002 up to 2010 are not comparable with the total provided for council, healtboard and total Scotland figures given. This is due to a correction of the later data, which affected mainly the older age groups. More details can be found on the [revisions](https://www.nrscotland.gov.uk/files//statistics/population-estimates/mid-year-corrections/correction-to-age-distribution-mid-year%20pop-estimates-2002-2010.pdf) section of the NRS website. Also note that the data for 2012, 2013, and 2014 are not comparable between the Historical Geographical Boundaries (2001 Data Zone based) and Current Geographical Boundaries (2011 Data Zone based) datasets. This is due to the correction of the errors that mainly affected age distribution in the mid-year population estimates. Following a user consultation, we have corrected the affected mid-2012, mid-2013 and mid-2014 population estimates for 2011 Data Zone based estimates only. The errors had no effect on the total population of Scotland. More details can be found on the [NRS website]( https://www.nrscotland.gov.uk/statistics-and-data/statistics/statistics-by-theme/population/population-estimates/2011-based-special-area-population-estimates/small-area-population-estimates/mid-2015-and-corrected-mid-2012-to-mid-2014/corrected-estimates-for-mid-2012-to-mid-2014).
Mid-year population estimates. Higher geographies are aggregated from 2001 Data Zones.
Population Estimates (Historical Geographic Boundaries)
Annual publication of mid-year population estimates by age and sex as at 30 June every year, where estimates for higher geographies are aggregated from 2001 Data Zones. For population estimates for 2011 Data Zones, see [here](http://statistics.gov.scot/data/population-estimates-current-geographic-boundaries) Data zones are the small area geography used by Scottish Government to allow statistics to be available across a number of policy areas. The data zone geography covers the whole of Scotland. Data zones were initially set up to nest within council area boundaries and to have a population of between 500 and 1,000 household residents. As much as possible, data zones were set up to contain households with similar social characteristics and to take into consideration physical boundaries. More information on data zone geography can be found on the [Scottish Government](http://www.gov.scot/Publications/2004/02/18917/33243) website. Following the 2011 Census the Scottish Government competed a consultation on the redrawing of data zone boundary and finalised the new data zones (2011 Data Zones) were published at the end of 2014. Intermediate zones are built up from data zones. Intermediate zones are the statistical small geographical areas designed to contain a population of between 2,500 and 6,000 household residents. More information on intermediate geography can be found on the [Scottish Government](http://www.gov.scot/Publications/2005/02/20732/53081) website.
Population estimates are not subject to scheduled revision. Revisions and corrections to previously published statistics are dealt with in accordance with the Scottish Government Statistician Group corporate policy statement on revisions and corrections - a copy of which is available on the [Scottish Government]( http://www.gov.scot/Topics/Statistics/About/CPSonRevisionsCorrections/Q/EditMode/on/ForceUpdate/on) website.
Data file for Population Estimates (Historical Geographic Boundaries)