I cannot answer that specific question, as I do not have that information in my brief. However, I undertake to investigate and shall write to the noble Lord. He refers to 20 years ago, since when I think that there has been a far greater global awareness of the huge significance of nuclear weapons. Although this country and others, as participators, support multilateral nuclear disarmament, there is clearly still a place for a nuclear deterrent in current times. However, he makes an interesting point and I shall investigate it.