Geography and time periods: statistics terms explained

Which countries and which twelve months a figure covers: UK or Great Britain, England and Wales, financial or calendar year.

Great Britain and the United Kingdom

Great Britain is England, Scotland and Wales. The United Kingdom is Great Britain plus Northern Ireland. Some statistics cover only one or the other.

Great Britain (GB) is England, Scotland and Wales. The United Kingdom (UK) is Great Britain plus Northern Ireland. Many official statistics cover the UK, but some cover only GB, England and Wales, or a single nation, because services and data systems differ.

Examples

ONS average weekly earnings covers Great Britain.
The Labour Force Survey headline estimates and GDP cover the UK.
Many health, education and justice statistics cover one nation, because those services are devolved.

Worked example

Suppose a hypothetical GB figure is 30 million and Northern Ireland adds 1 million, giving 31 million for the UK. Comparing a GB figure for one year with a UK figure for another would show an apparent change of over 3% that is only a difference in coverage.

How it trips up claims

"UK" is often used loosely for figures that cover only England or GB. Check the coverage line in the source.
Per head figures need the population for the same coverage.

See how to compare the four nations.

Also searched as: GB vs UK, difference between Great Britain and UK, United Kingdom vs Great Britain, British Isles

Official definitions: ONS: UK geographies · ONS: Average weekly earnings in Great Britain, latest bulletin

England and Wales

A single legal jurisdiction, so crime, courts, prisons and death registration statistics are often published for England and Wales together.

England and Wales form a single legal jurisdiction, while Scotland and Northern Ireland have their own legal systems. Statistics tied to the law, courts, police and registration are therefore often published for England and Wales combined.

Examples

Crime Survey for England and Wales and police recorded crime.
Prison population statistics from the Ministry of Justice.
Death registrations published by the ONS for England and Wales; Scotland and Northern Ireland register deaths separately.

Health and education are devolved, so many of those statistics are for England alone, even when the legal jurisdiction is shared.

Worked example

A hypothetical England and Wales total of 600,000 offences combines roughly 570,000 in England and 30,000 in Wales. Adding Scotland's figure to make a "UK" total is risky, because offence definitions and counting rules differ between jurisdictions.

How it trips up claims

"Britain's prison population" is often an England and Wales figure. Check the coverage.
Comparing Scotland's figures with England and Wales figures needs care about definitions.

Also searched as: England & Wales, E&W, England and Wales jurisdiction, why England and Wales statistics

Official definitions: ONS: Crime in England and Wales, latest bulletin · ONS: Administrative geography

Financial year

The UK government's accounting year, running from 1 April to 31 March. Written as 2025-26 or FYE March 2026. The tax year runs 6 April to 5 April.

The UK government's financial year runs from 1 April to 31 March. It is usually written as, for example, 2025-26 or "financial year ending (FYE) March 2026". Public spending, borrowing and many departmental statistics use it. The personal tax year is slightly different: 6 April to 5 April.

Worked example

A hypothetical department spends £10 billion in January to March and £30 billion in April to December of the same calendar year. Its spending in that calendar year is £40 billion, but those months fall into two different financial years, so neither financial-year total equals £40 billion.

How it trips up claims

Comparing a financial-year figure with a calendar-year figure mixes periods that overlap by nine months.
"Last year" in a public finances statement usually means the last complete financial year.
DWP poverty statistics and many NHS and education statistics use financial or academic years, which differ again.

Also searched as: fiscal year, FYE, tax year, April to March, 2025-26 meaning

Official definitions: ONS: Public sector finances, latest bulletin · GOV.UK: Income Tax rates and allowances (tax year)

Calendar year

January to December. Used for GDP annual totals, registered deaths and many international comparisons, unlike the April to March financial year.

A calendar year runs from 1 January to 31 December. Annual GDP, many international datasets, and registered births and deaths are commonly published on a calendar-year basis.

Other years you will meet

Financial year: April to March, used for public finances.
Academic year: usually September to August, used for schools and universities.
"Year ending" a month: a rolling twelve months, used for crime and migration.

Worked example

A hypothetical series counts 100 events from January to March and 300 from April to December in year one, then 120 from January to March in year two. The calendar-year total for year one is 400. The financial year April (year one) to March (year two) is 420. Same data, two different "annual" totals.

How it trips up claims

A "record year" may depend on which year definition is used. Check the period in the table heading.
International bodies such as the IMF and OECD mostly use calendar years, so UK financial-year figures need converting before comparison.

Also searched as: January to December, calendar year vs financial year, annual total

Official definitions: ONS: Quarterly national accounts, latest bulletin · ONS: Mortality statistics in England and Wales, quality and methodology information

Tax year

The UK personal tax year runs from 6 April to 5 April the following year. It differs from the government's financial year, which runs from 1 April.

The tax year for UK personal taxes such as Income Tax and Capital Gains Tax runs from 6 April one year to 5 April the next. It is written as, for example, 2026 to 2027 or 2026-27. Rates, allowances and thresholds normally change at the start of the tax year.

Why it matters when checking a claim

Not the same as the financial year. Public finance statistics use the year from 1 April to 31 March. The difference of a few days rarely changes totals much, but the labels can be confused.
Collected later. Tax due for one tax year may be paid in a later one, especially self assessment, so receipts in a year are not the same as liabilities for that year. HMRC statistics say which basis they use.
Some taxes differ. Corporation Tax is based on companies' accounting periods and the financial year.

See UK income tax bands.

Also searched as: UK tax year dates, 6 April tax year, tax year 2026 to 2027, why does the tax year start on 6 April

Official definitions: GOV.UK: Income Tax · HMRC: Tax and NICs receipts for the UK

Academic year

The year used in education statistics: usually September to August for schools and August to July for universities.

The academic year is the year used for most education statistics. For schools in England, Department for Education statistics are labelled by academic year, such as 2025/26, covering the year that starts in September. Higher education statistics generally use a year running from 1 August to 31 July.

Why it matters when checking a claim

Labels can mislead. "2025/26" in school statistics is not the same twelve months as the 2025-26 financial year used for school funding.
Census points within the year. Many school counts come from the January school census, so a pupil number for 2025/26 is a snapshot taken in January 2026.
Exam results are published in the summer but labelled with the academic year in which pupils sat them.
Scotland, Wales and Northern Ireland publish their own education statistics with their own reference dates.

See the Explore Education Statistics guide.

Also searched as: school year, academic year uk, academic year dates, 2025/26 academic year

Official definitions: DfE: Schools, pupils and their characteristics · DfE: Pupil absence in schools in England

ITL regions (International Territorial Levels)

The UK's official system of statistical regions, which replaced the EU's NUTS system. ITL1 is the nine English regions plus Scotland, Wales and Northern Ireland.

International Territorial Levels (ITL) are the geographies the ONS uses to publish regional statistics such as GDP, GVA and productivity. They replaced the EU's NUTS classification from 2021 and keep the same three-level structure:

ITL1: the nine regions of England (such as the North East and London) plus Scotland, Wales and Northern Ireland.
ITL2: groups of counties or city regions.
ITL3: individual counties, unitary authorities or groups of them.

Why it matters when checking a claim

An ITL area is not always the same as a council, combined authority or mayoral area. Check which boundary a figure uses.
Boundaries are periodically updated, which can affect comparisons over time.

See how to find local data for your area and the regional pages.

Also searched as: ITL1, ITL2, ITL3, NUTS regions, UK statistical regions

Official definitions: ONS: International geographies · ONS: Regional economic activity by gross domestic product

Lower layer super output area (LSOA)

A small statistical area in England and Wales, typically home to 1,000 to 3,000 people, used to publish local data such as deprivation and census results.

A lower layer super output area (LSOA) is a small geographic unit used by the ONS to publish statistics for neighbourhoods in England and Wales. Each usually has between 1,000 and 3,000 residents (400 to 1,200 households). LSOAs nest inside larger middle layer super output areas (MSOAs). Scotland uses data zones and Northern Ireland uses its own small areas.

Why it matters when checking a claim

Deprivation rankings. The English and Welsh indices of deprivation rank LSOAs, not councils. A claim that a town is among the "most deprived" may refer to a few of its neighbourhoods.
Small numbers. With so few residents, rates can swing widely and counts may be rounded or suppressed. See data suppression.
Boundary updates. LSOAs were revised after the 2021 census, so check which version a dataset uses.

See how to find local data for your area.

Also searched as: LSOA, MSOA, super output area, LSOA meaning, data zone

Official definitions: ONS: Statistical geographies · ONS: Census