Polo handicap

A polo handicap is a system created by Henry Lloyd Herbert, the first president of the United States Polo Association, at the founding of the USPA in 1890 so teams could be more evenly matched when using players with varying abilities.
The players are rated on a scale from minus-2 to 10. Minus-2 indicates a novice player, while a player rated at 10 goals has the highest handicap possible. It is so difficult to attain a 10-goal handicap that there are fewer than two dozen in the world, and about two-thirds of all players handicapped are rated at two goals or less. Currently, most living ten-goal players are Argentine, with few exceptions.
Handicaps of five goals and above generally belong to professional players. It is not (nor has it ever been) an estimate of the number of goals a player might score in a game, but rather of the player's worth to his or her team. It is the overall rating of a player's horsemanship, team play, knowledge of the game, strategy, and horses. At one time, polo was the only sport in the world that considered sportsmanship when rating a player.
In matches played by "handicapped" players (as opposed to open competition, where handicaps are not considered), the handicaps of all four players are totaled. If the total handicap of a team is more than that of the team against which they are playing, the difference is added to the scoreboard. For example, if the Mounties polo team has a total handicap of six goals and the Tayto team has a handicap of four goals, Tayto would begin the match with a two-goal advantage.
A player's handicap is usually assessed by a committee at the authorizing club of his country. A professional player may be assigned an equivalent rating in countries where he competes.
Though standards are similar, the ratings may be expressed differently. "e.g.:"
Argentina: 0 to 10
USA: C (-2), B (-1), B+ (-0.5), A (0), A+ (0.5), 1.0, 1.5, 2 to 10
England: -2 to 10.