Analysis unit

Persons, households, and dwellings Excludes Northern Ireland; age is grouped into categories

UNITS IDENTIFIED: - Dwellings: Yes - Vacant Units: No - Households: yes - Individuals: yes - Group quarters: Yes

UNIT DESCRIPTIONS: - Dwellings: no - Households: A household comprises either one person living alone or a group of people not necessarily related, living at the same address with common housekeeping - that is, sharing at least one meal a day or sharing a living room or sitting room. People staying temporarily with the household are included. - Group quarters: Yes

Universe

All persons (members of the household, including visitors, employees and boarders) who are present at midnight on the night of Sunday, 23rd April, 1961, in the dwelling, and alI persons who arrive at the dwelling and join the household on Monday, 24th April, 1961, before the collection of the schedule, and who have not been enumerated elsewhere.

Kind of data

Population and Housing Census [hh/popcen]

Sampling procedure

MICRODATA SOURCE: Office of Population and Surveys for England and Wales

SAMPLE SIZE (person records): 495581.

SAMPLE DESIGN: Original data from which the sample was extracted is itself a systematic sample of every 10th household, selected during the data collection process, and that received the long form. The original data was then stratified by household type and sorted geographically. One in ten households was subsequently systematically excluded. Persons living in communal establishments or in households with more than nine residents were excluded. Finally, a 0.95% sample of households was extracted by selecting randomly 1-in-9 households from the remaining long form respondents. Individuals within communal establishments and those in households with more than nine residents were selected separately from data ordered by geography. No weighting was applied. NOTE: The sample excludes Northern Ireland. It includes England, Scotland and Wales.

Mode of data collection

Face-to-face [f2f]

Research instrument

Two questionnaires: a long form applied to ten percent of the poulation and a short form to the other ninety percent. Each of them collected information from all persons, private households, and persons absent from the household.

In 1821, the population of the island of Ireland was just over 6.8 million people. During this time, the entire island was a part of the United Kingdom of Great Britain and Ireland, after both islands were united by the Act of Union in 1800. The population enjoyed steady growth between 1821 and 1841, and it rose by almost 1.4 million people in this time, however the Great Famine, which lasted from 1845 to 1849, had a devastating impact on the population, causing it to drop from 8.18 million in 1841 to 6.55 million in 1851. If applying modern-day borders, the population of Northern Ireland was not growing as fast as the population of the Republic of Ireland before 1841, however it was not as severely affected by the famine, which was hardest felt in the east and south. The Great Hunger The famine was caused by a Europe-wide potato blight that contributed to mass starvation and death throughout the continent, although it's impact on Ireland was much harsher than anywhere else. The potato blight affected Ireland so severely as the majority of potatoes in Ireland were of a single variety which allowed the disease to spread much faster than in other countries. As the potato blight spread, the population became increasingly dependent on dairy and grain products, however a lot of these resources were relocated by the British military to combat food shortages in Britain. Due to disproportional dependency on potatoes, and mismanagement by the British government, over one million people died and a further one million emigrated. The Great Famine lasted from just 1845 to 1849, but it's legacy caused almost a century of population decline, and to this day, the overall population of Ireland has never exceeded it's pre-famine levels. Decline continues through partition The population decline continued well into the twentieth century, during which time the Republic of Ireland achieved independence from the British Empire. After centuries of fighting and rebellion against British rule, Irish nationalists finally gained independence from Britain in 1921, although the six counties with the largest Protestant populations formed Northern Ireland, which is still a part of the United Kingdom today. Although there was much conflict in Ireland in the twentieth century which claimed the lives of thousands of people (particularly during the Northern Irish Troubles), and despite Ireland's high emigration rate, the overall population began growing again in the second half of the 1900s. Recovery The population of the Republic of Ireland was at it's lowest in 1961, with 2.8 million people, which is almost four million fewer people than before the famine. Since then it has grown consistently, reaching 4.6 million in 2011 and expected to reach 5 million people by 2020. In Northern Ireland, the population began growing again from the beginning of the 1900s, but growth has been very slow. The only time it fell was in the 1970s, at the peak of The Troubles, where high unemployment and violence contributed to a lower birth rate and an increase in emigration. From the 1980s onwards, living standards improved and the population began growing again, reaching 1.8 million people in 2011.

ONS Mid-year estimates (MYE) of resident populations for London boroughs are available in the following files:

Read the GLA Intelligence Updates about the MYE data for 2011 and 2012.

Mid-year population by single year of age (SYA) and sex, for each year 1999 to 2014.

ONS mid-year estimates data back to 1961 total population for each year since 1961.

These files take into account the revised estimates released in 2010.

Ward level Population Estimates

London wards single year of age data covering each year since 2002.

Custom Age Range Tool

An Excel tool is available that uses Single year of age data that enables users to select any age range required.

ONS policy is to publish population estimates rounded to at least the nearest hundred persons. Estimates by single year of age, and the detailed components of change are provided in units to facilitate further calculations. They cannot be guaranteed to be as exact as the level of detail implied by unit figures.

Estimates are calculated by single year of age but these figures are less reliable and ONS advise that they should be aggregated to at least five-year age groupings for use in further calculations, onwards circulation, or for presentation purposes. (Splitting into 0 year olds and 1-4 year olds is an acceptable exception).

ONS mid-year population estimates data by 5 year age groups going all the way back to 1981, are available on the NOMIS website.

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For a detailed explanation of the methodology used in population estimates, see papers available on the Population Estimates section of the ONS website. Additional information can also be obtained from Population Estimates Customer Services at pop.info@ons.gsi.gov.uk (Tel: 01329 444661).