Jordan operates a rentier economy based largely on foreign aid, investment, and remittances. Jordan heavily depends on its highly skilled workforce in the oil-rich Persian Gulf to send back money to help support thousands of Jordanian families. Consequently, its economic fortunes are tied to events in the international community. Although the standard of living in Jordan is significantly higher than other countries with similar incomes, having among the best education and healthcare systems in the Middle East, many Jordanians opt to work abroad because of soaring costs of living and high unemployment in their native country. Jordan is dependent on those remittances which have accounted for nearly 20% of GDP since 1975. Jordan's dependence has had detrimental consequences. Following Iraq's 1990 invasion of Kuwait hundreds of thousands of Palestinians were expelled from other Arab nations. For Jordan this resulted in the significant loss of remittance revenue.