The pilot reported he had dropped a group of skydivers and was descending to land after his final flight of the day. The airplane was about 1,500 to 1,700 feet above ground level, and about 1 1/4 miles from the airport when the engine experienced a total loss of power. The pilot made an emergency off field landing to an open field and the airplane sustained substantial damage to the fuselage. The pilot reported that the fuel gauges were unreliable and he had incorrectly estimated the fuel quantity remaining. He also reported that he thought the loss of engine power was due to him running out of fuel. A postaccident examination of the airplane showed 1 to 2 gallons of fuel remaining in each fuel tank.