NEW ORLEANS (AP) — The federal government will offer 77.3 million acres in the Gulf of Mexico for oil and gas exploration and development on Aug. 15.

An Interior Department statement Friday said the lease sale will include all 14,474 unleased tracts. They're in water 3 to 231 miles (5 to 370 kilometers) offshore, and in water from 9 feet to more than 2 miles (three to 3,400 meters) deep.

From 1984 until last year, one sale covered areas off Louisiana, Mississippi, Alabama and Florida, and one leased tracts off Texas. Dwindling numbers of bidders prompted consolidation.

Shortly before the first consolidated sale last August, the government dropped royalty rates for tracts in less than 200 meters (660 feet) of water to 12.5 percent because of low prices and the marginal nature of remaining tracts. The rate is 18.75 percent for other leases.