HC Deb 13 July 1965 vol 716 c36W
30. Mr. McNair-Wilson

asked the Minister of Power how many unprofitable collieries have become profitable in the last six weeks.

Mr. Frederick Lee

I understand that information in the form requested is not available, and that the National Coal Board judges changes in the profitability of pits over fairly long periods to allow for many temporary factors such as seasonal movements, price variations, holidays and geological difficulties.