The proportion is less than 5% in Powys, The Vale of Glamorgan and Monmouthshire, but is over 15% in Blaenau Gwent.
Mae’r gyfran yn llai na 5% ym Mhowys, Bro Morgannwg a Sir Fynwy, ond mae dros 15% ym Mlaenau Gwent.