1946, BST operated as normal (from April to October) but in 1947, for a single year, BDST was re-introduced with effect from 13 April (BST having started on 16 March). After four months of BDST the clocks were put back by an hour on 10 August (to BST) and by another hour on 2 November (to GMT). An inquiry during the winter of 1959–60, in which 180 national organisations were consulted, revealed a slight preference for a change to all-year GMT+1, but instead the length of summer time was extended as a trial. A further inquiry during 1966–1967 led the government of Harold Wilson to introduce the British Standard Time experiment, with Britain remaining on GMT+1 throughout the year. This took place between 27 October 1968 and 31 October 1971, when there was a reversion to the previous arrangement. Analysis of accident data for the first two years of the experiment, published by HMSO in October 1970, indicated that while there had been an increase in casualties in the morning, there had been a substantially greater decrease in casualties in the evening, with a total of around 2,700 fewer people killed and seriously injured during the first two winters of the experiment, at a time when about 1,000 people a day were killed or injured on the roads. However, the period coincided with the introduction of drink/drive legislation; the estimates were later modified downwards in 1989. The trial was the subject of a House of Commons debate on 2 December 1970 when, on a free vote, the House of Commons voted by 366 to 81 votes to end the experiment. Debates on reform Campaigners, including the Royal Society for the Prevention of Accidents (RoSPA) and environmental campaigners 10:10, have made recommendations that British Summer Time be maintained during the winter months, and that a "double summertime" be applied to the current British Summer Time period, putting the UK one hour ahead of GMT during winter, and two hours ahead during summer. This proposal is referred to as "Single/Double Summer Time" (SDST), and would effectively mean the UK adopting the same time zone as European countries such as France, Germany, and mainland Spain (Central European Time and Central European Summer Time). RoSPA has suggested that this would reduce the number of accidents over this period as a result of the lighter evenings. RoSPA have called for the 1968–71 trial to be