GDP stands for Gross Domestic Product, and it attempts to show the economic state of the country in a number.
It's a measure of how the economy has grown or contracted over a three month period.
The level of GDP is measured in three ways: the value of the goods and services produced by the economy, the value of goods and services purchased by households and the government, and the income generated in terms of profit and wages.
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Feeling humid with heavy showers and thunderstorms moving north overnight into Sunday.
Four people, including three children, were taken to hospital to be checked for smoke inhalation.
Heavy rain and thunderstorms will affect many parts of Wales this weekend - particularly during Saturday evening.