Peter Stokes, from the Office for National Statistics, says changing numbers of Welsh speakers in different parts of the country can partly be explained by migration within Wales.
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Through this evening and overnight it will remain cloudy with some persistent rain and drizzle by dawn.
A couple from Wales, who moved to South Africa to live 40 years ago, have been killed on their farmland estate there, police have confirmed.
Our Valleys Correspondent Hannah Thomas has been spending time discovering why the people who live in the Valleys love their communities.