A foreign exchange trader working for a bank enters into a long forward contract to buy one million pounds sterling at an exchange rate of 1.6000 in three months. At the same time, another trader on the next desk takes a long position in 16 three-month futures contracts on sterling. The futures price is 1.6000 and each contract is on 62,500 pounds. Within minutes of the trades being executed the forward and the futures prices both increase to 1.6040. Both traders immediately claim a profit of $4,000. The banks systems show that the futures trader has made a $4,000 profit, but the forward trader has made a profit of only $3,900. The forward trader immediately picks up the phone to complain to the systems department. Explain what is going on here. Why are the profits different?