Abstract: A method and apparatus for trading a standardised contract. The contract obliges the seller to make delivery to the exchange of a standardised debt product on the delivery date of the contract for a price given by the exchange determined settlement price and a conversion factor. The contract further requires to take delivery from the exchange of said debt obligation for the same price. The contract further requires the buyer or seller to make margin payments to the exchange on each trading day, or with a longer period, based on the price movements of the contract during that trading day or period if so required by the trading rules. The contract further obliges the exchange to make similar payments to the buyer or seller if they are entitled to such payments under the trading rules.