In horse racing, the term purse distribution may refer to the total amount of money paid out to the owners of horses racing at a particular track over a given period of time, or to the percentages of a race's total purse that are awarded to each of the highest finishers. This article focuses on the latter definition. Background Prior to the 1970s, only the owners of the first four finishers in a horse race in the United States typically received any money at all. In Thoroughbred racing, it was common for 65% of the race's purse was awarded to the winner, with the second, third and fourth horses earning 20%, 10% and 5% respectively. This procedure had some drawbacks, especially in the event of inclement weather — owners would often seek to "scratch," or withdraw their horses from a race, if the track was wet, and even more so if rain forced a scheduled turf, or grass race, to be moved to the main, or dirt, track. It was largely in an effort to encourage larger fields in these circumstances that many American state racing associations began changing their purse-distribution formats during the last three decades of the 20th century. One frequently-implemented reform was to include horses finishing fifth in the purse distribution; the method most often employed for doing this was to award 60% of the purse to the winner, 20% to second, 11% to third, 6% to fourth and 3% to fifth, a format still observed by many tracks today. Some tracks even went so far as to include the sixth-place runner in the purse as well; most often, this resulted in 60% being given to the winner, 20% to second, 10% to third, 5% to fourth, 3% to fifth and 2% to sixth. In 1975, the state of Florida enacted a purse-distribution format that has had revolutionary implications for the sport of horse racing in the United States: Its adopted plan provided 1% of the purse to all finishers in the race lower than fourth; this meant that the percentages paid out to the horses finishing second, third and fourth (but not first) became variable, depending upon the size of the field. For example, if a race had twelve starters, 60% of the purse went to the winner, 18% to second, 10% to third, 4% to fourth and 1% each to fifth through twelfth; with only