<P> In 1996, the three - year period was reduced to two years, with the current year now counting double . Points were extended to more of the field, beginning in 2000, and were no longer restricted to integer values . Beginning in September 2001, the tapering system was changed so that instead of the points for each result being doubled if they occurred in the most recent 12 months, one eighth of the initial "multiplied up" value was deducted every 13 weeks . This change effectively meant that players could now be more simply described as being awarded 100 points (not 50) for winning a major . Beginning in 2007, the system holds the points from each event at full value for 13 weeks and then reduces them in equal weekly increments over the remainder of the two - year period . </P> <P> At first only the Championship Committee of the Royal and Ancient used the rankings for official purposes, but the PGA Tour recognized them in 1990, and in 1997 all five of the then principal men's golf tours did so . The rankings, which had previously been called the Sony Rankings, were renamed the Official World Golf Rankings at that time . They are run from offices in Virginia Water in Surrey, England . </P> <P> Simply put, a golfer's World Ranking is obtained by dividing their points total by the number of events they have played, which gives their average . Players are then ranked; a higher average yields a higher rank . </P> <P> The first stage in the calculation is the ranking of each event . For most events the ranking depends on the current world rankings of the participating golfers and the participation of the leading golfers from the "home tour". </P>

How many world ranking points for winning the masters