The data for the GDP of the United Kingdom (UK) presented on this web site consists of 1) official government series that start in 1948 and 2) data linked to those series that have been constructed by economic historians and extended back to 1700. There are two versions of the data to download that deal with the inclusion of data for Ireland; they differ for the years before 1921.

The “Official” series. The concept of measuring GDP is a creation of the middle of the 20th century. Official government series of the UK GDP have been published annually since 1953 and quarterly since 1961. They begin with the year 1948.

We also provide a link to ALL the versions of the official GDP post-1947 series. Here you will find 55 versions of the annual data from 1959 on and over 200 versions of the quarterly data as published from 1961 to the present.

These series change from year to year for a variety of reasons that we have discussed elsewhere. An article discussing the changes in the official series during the post war period can be found here Vintage Does Matter, The Impact and Interpretation of Post War Revisions in the Official Estimates of GDP for the United Kingdom.

The “Historical” series. For most of its history, the UK consisted of England, Wales, Scotland, and Ireland. Economic historians have created data sets for each of these different countries, some that extend back to the thirteenth century. Many of these series are published by the Bank of England and have been provided to us. The source document at the bottom of this page gives a detailed description of the series they have provided to us.

The problem of how to count with Ireland.

All of Ireland became part of the UK with the Act of Union 1800. Northern Ireland and Southern Ireland were created in 1920 by The Government of Ireland Act. The following year The Anglo-Irish Treaty defined the United Kingdom as including only the six counties of Northern Ireland.

For the benefit of our users, we present two versions of the data. The first is the series from 1700 to the present that is consistent in terms of the geographical area it is measuring. That is, it is for England, Wales, Scotland and Northern Ireland. It is call the Consistent Series. Prior to 1801 Northern Ireland is assumed to be a constant share of UK GDP given a lack of available data.

The second series is from 1801 to the present and is consistent in terms of political units that are measured. This measures what was called the UK at any point in time, that is England, Wales, Scotland and all of Ireland up to 1920 and then only Northern Ireland. It is called the Historic Series. Note that the two series are the same for data from 1921 to the present. Because this series contains a break in 1920, it is not suitable for time series analysis. It is useful,however, as a measure of the overall size of the UK economy at a particular point in history. For example it is an estimate of the income or tax base available at any one time to fund public spending or to service the national debt.

Definitions

Gross Domestic Product (GDP) is the market value of all final goods and services produced within a country during a given time period. There are two ways to measure GDP:

• Nominal GDP is the value of production at current market prices, reported in millions of British pounds.
• Real GDP is the value of nominal GDP in a given base year’s prices reported in millions of British pounds at constant (2019) market prices.

The GDP Deflator is the price index used to measure changes in the overall level of prices for the goods and services that make up GDP. It is simply the ratio of nominal to real GDP times 100. It is also 100 times the ratio of nominal GDP per capita (per-capita GDP at current market prices) to real GDP per capita (per-capita GDP at constant (2019) market prices).

GDP per capita is calculated by dividing either nominal or real GDP for a given year by the population in that year.

For a detailed explanation of the data presented here, please read:

"Notes on Three Centuries of UK GDP and Seven Centuries of English GDP".

Ryland Thomas and Samuel H. Williamson, "What Was the U.K. GDP Then?" MeasuringWorth,
URL: http://www.measuringworth.com/ukgdp/