asked the Chancellor of the Exchequer what is the current yield of petroleum revenue tax, together with the estimated yield at 65 per cent. and 70 per cent.

The yield of petroleum revenue tax in 1980–81 at various rates would be:

asked the Chancellor of the Exchequer, for fields above the tapering tranche of petroleum revenue tax, what is the Government take at the proposed new rate on each extra £ sterling of revenue.

87·4 per cent.