Traditional industries such as sugar refining, rum distilling, and tobacco processing are well established in St. Kitts. The island has also witnessed the steady growth of newer manufacturing interests in recent years, leading to a 23.8 percent share of the GDP in 1999. In fact, 4 industrial sites have been developed, specializing in heavy machinery, electronic components, and other manufactured goods destined for the North American market. Garment manufacturing has expanded since the mid-1990s and now accounts for a large share of export earnings. Upgrading the Port Zante harbor complex in Basseterre enables large container ships to call, further enhancing St. Kitts' attractiveness as an offshore manufacturing base. According to the World Bank, manufactured exports were valued at US$20 million in 1998 and 1999, suggesting that this sector was the least affected by hurricane damage. There is no manufacturing on Nevis. In 1997 the IMF estimated that 1,290 people worked in the manufacturing sector.