Chad’s landlocked location results in high transportation costs for imported goods and dependence on neighboring countries. Oil and agriculture are mainstays of Chad’s economy. Oil provides about 60% of export revenues, while cotton, cattle, livestock, and gum arabic provide the bulk of Chad's non-oil export earnings. Chad relies on foreign assistance and foreign capital for much public and private sector investment. The services sector contributes about one-third of GDP and has attracted foreign investment mostly through telecommunications and banking. Chad’s fiscal position is encumbered by declining oil prices, though high oil prices and strong local harvests supported the economy in recent years. Nearly all of Chad’s fuel is provided by one domestic refinery, and unanticipated shut-downs occasionally result in shortages. The country regulates the price of domestic fuel, providing an incentive for black market sales. Chad's investment climate remains challenging due to limited infrastructure, a lack of trained workers, extensive government bureaucracy, and corruption. Chad obtained a three-year extended credit facility from the IMF in 2014 and was granted debt relief under the Heavily Indebted Poor Countries Initiative in April 2015..