The Danes secured control over the southern Virgin Islands of Saint Thomas, Saint John, and Saint Croix during the 17th and early 18th centuries. Sugarcane, produced by African slave labor, drove the islands' economy during the 18th and early 19th centuries. In 1917, the US purchased the Danish holdings, which had been in economic decline since the abolition of slavery in 1848. On 6 September 2017, Hurricane Irma passed over the northern Virgin Islands of Saint Thomas and Saint John and inflicted severe damage to structures, roads, the airport on Saint Thomas, communications, and electricity. Less than two weeks later, Hurricane Maria passed over the island of Saint Croix in the southern Virgin Islands, inflicting considerable damage with heavy winds and flooding rains.
Tourism, trade, and other services are the primary economic activities, accounting for nearly 60% of the Virgin Island's GDP and about half of total civilian employment. The islands host nearly 3 million tourists per year, mostly from visiting cruise ships. The islands are vulnerable to damage from storms. The agriculture sector is small, with most food being imported. Industry and government each account for about one-fifth of GDP. The manufacturing sector consists of rum distilling, electronics, pharmaceuticals, and watch assembly. A refinery on St. Croix, one of the world’s largest, processed 350,000 barrels of crude oil a day until it was shut down in February 2012, after operating for 45 years.
Federal programs and grants, totaling $241.4 million in 2013, contributed 19.7% of the territory’s total revenues. The economy declined in 2013, due to decreases in exports resulting from the loss of refined oil products. Nevertheless, the economy remains relatively diversified. Along with a vibrant tourism industry, rum exports, trade, and services will be major income sources in future years.