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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A cloudy picture to start with but also some sunny spells around. Feeling rather humid out there.
This evening will stay cloudy but dry and the night will be mild and humid across the country.
An ITV News investigation has revealed the worrying scale of contamination and pollution in our rivers from farm waste.