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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Those watching Euro 2016 games in Wales have seen alcohol marketing almost once a minute during play, according to new research.
Williams has had scans after he suffered a shoulder injury against Northern Ireland.
Chris Bryant was speaking on ITV's Good Morning Britain following his resignation as Shadow Leader of the House of Commons.