This volatility is due to the impact on the supply of lambs due to bad weather over the summer and autumn and lamb imports which are significantly cheaper than the home product.
Y rheswm am hynny yw effaith y tywydd ar y cyflenwad ŵyn dros yr haf a’r hydref diwethaf a’r ffaith bod cig oen sydd wedi’i fewnforio gymaint rhatach nag ŵyn Cymru.