scores are subtracted from the +620 score and the result entered in the point-differential cells. For each point differential, the IMP look-up table is used to determine the IMPs gained. For example, the differential of 720 equates to 12 IMPs, because it falls in the range of 600 to 740 in the IMP table. Adding the IMPs gained gives a total of 37. To determine the average IMPs gained, divide the total by the number of competitors (37 divided by 4) to arrive at 9.25 as the averaged cross-IMP score. Victory Point scoring In some events (for example, Swiss Teams), a further normalization to reduce the effect of large swings is applied to the International Match Point scores. A specific number of Victory Points, either 20 or 30, are divided between the two teams in accordance with the following scales: 20-point scale Example: A team winning by 12 IMPs would receive 15 VPs and their opponents 5. 30-point scale Example: A team winning by 12 IMPs would receive 25 VPs and their opponents 5. History of contract bridge scoring Scoring of tricks in notrump contracts In the 1932 Laws of Contract Bridge, notrump tricks bid and made, and undoubled notrump tricks made but not bid, score 30, 40, 30, 40, 30, 40, 30. In 1935 this became 40, 30, 30, 30, 30, 30, 30. Scoring of undertricks Until 1987 Redoubled undertricks have always scored twice as much as the same doubled undertricks. After 1987 A change to the scoring of the fourth and subsequent non-vulnerable undertricks, from 200 each to 300 each, was made in 1987 after a hand in the finals of the 1981 Bermuda Bowl. Munir Attaullah and Jane Alam Fazli, playing for Pakistan, reached a vulnerable 7 contract, which would have scored them 2210. But their non-vulnerable opponent Jeff Meckstroth, playing for USA, calculated that down 11 would cost only 2100 points and thinking he might do better than that, sacrificed in 7 on a weak hand with five spades to the jack; this was doubled and went down nine for a score of -1700. The 510 point differential resulted in an 11 IMP swing in his team's favor. The 1987 change in scoring increased the penalty for down nine when doubled and not vulnerable from -1700 to -2300. Also, the "insult bonus" in rubber bridge for making a redoubled contract used to be only 50. This