Definitions for "PERCENTAGES"
Keywords:  bookies, odds, punter, aiming, eleven
BOOKIES set their odds according to the mathematical probabilities of events happening. If they were not aiming to make a profit, the probabilities would add up to 100%. But because the bookies want to make money from betting, they make their odds add up to more than 100%, which gives them a profit margin. The lower the PERCENTAGE that bookies are betting to, the lower their theoretical profit on the event will be.
Bookmakers set their odds according to percentages, the lower the percentage, the better deal the punter is getting. If the bookies were not aiming to make a profit, they would operate at 100% but because they want to make money from bookmaking they typically operate at 110% with their prices. For example, in a two horse race of equal ability, both should be priced at even money (£2.00 = 50%). This means the book is operating at 100% - i.e two horses at £2.00 = 50% x 2 = 100. However, because the bookmaker wants to make money, he will offer 4/5 (£1.80) for either horse to win. As a percentage, £1.80 stands at 55.5% meaning the book is 111% and assuming the bookmaker lays both sides evenly, he should make an eleven per cent profit.