An investor has just entered 3 short oil futures contracts at a futures price of $46 per barrel. The size of each contract is 1,000 barrels. The initial margin is $6,750 and the maintenance margin is $4,500 per contract. A week after opening the position the futures price rises to $49 per barrel. What is the balance of the margin account at the end of the week? (Assume that no margin call has occurred over this period and your answer should be to the nearest dollar, without the dollar sign.)