Providing Incentives to Spur Efficient Oil and Gas Development: The President recently directed the Department of Interior to determine the acreage of public lands (onshore and offshore) that have been leased to oil and gas companies and remain undeveloped. More than 70 percent of the tens of millions of offshore acres under lease are inactive—including almost 24 million inactive leased acres in the Gulf of Mexico, where an estimated billion barrels of oil and trillion cubic feet of natural gas of technically recoverable resources are going unused. Onshore, about 57 percent of leased acres –.