It is extraordinary that Opposition Members continue to knock British achievements. North sea oil revenues have contributed to the reduction of overseas debt and of the public sector borrowing requirement as a share of the gross domestic product, thus freeing resources for private investment. Our net overseas assets rose from £12½ billion at the end of 1978 to £112 billion at the end of 1989. That is the highest proportion of all major countries as a percentage of GDP and it is no mean achievement.