the main cities. Coupled with terrorist bombings at the Port of Aden in 2000 and 2002, the threat of kidnappings presents a significant deterrent to tourism. As recently as September 2006, tribesmen in the Shabwa province, east of Sanaa, kidnapped four French tourists on their way to Aden; the tourists were freed two weeks later. In October 2006, the U.S. Department of State reiterated previous warnings to U.S. citizens, strongly urging them to carefully consider the risks of traveling to Yemen. Britain's Foreign Office has issued a similar advisory. Recent statistics for tourist arrivals in Yemen are not available, but the number of tourist arrivals rose to 274,000 in 2004 from 155,000 in 2003. Labor According to the US government, the agriculture and herding sector employs the majority of Yemen's working population (54.2 percent in 2003). Industry, services, construction, and commerce collectively account for less than 25 percent of the labor force. According to the World Bank, Yemen's civil service is characterized by a large, poorly paid work force and inadequate salary differential between high and low skilled jobs to attract and retain qualified workers. In 2004, the government increased civil service salaries by 20 to 40 percent in order to alleviate the impact of anticipated economic reforms that were never implemented. The result was a 20 percent rise in wage costs; civil service wages constituted 7 percent of gross domestic product (GDP) in 2004. The 2005 budget reduced economic subsidies, but in exchange the new budget required the government to make various concessions, including increasing civil service wages another 10 to 15 percent by 2007 as part of a national wage strategy. The economic assistance package that the International Monetary Fund (IMF) pledged to Yemen is contingent on the implementation of civil service reform, which the government has resisted because of the country's estimated 20 to 40 percent unemployment rate. In 2004, the government claimed to have reduced the civil service labor force through retirements and layoffs, but it appears that the large salary increases have lessened the impact of any reforms. The IMF has stated that civil service salaries as a component of GDP should be reduced by 1 to 2 percent, a level that can only be achieved with continued reductions in the size of the civil service. It is unclear whether the national wage strategy, which may succeed in streamlining the system and removing irregularities, will