Occupying the northeast corner of the African continent, Egypt is bisected by the highly fertile Nile valley, where most economic activity takes place. Egypt's economy was highly centralized during the rule of former President Gamal Abdel NASSER but opened up considerably under former Presidents Anwar EL-SADAT and Mohamed Hosni MUBARAK. Cairo from 2004 to 2008 pursued business climate reforms to attract foreign investment and facilitate growth. Poor living conditions and limited job opportunities for the average Egyptian contribute to public discontent, a major factor leading to the January 2011 revolution that ousted Mubarak. The uncertain political, security, and policy environment since 2011 caused economic growth to slow significantly, hurting tourism, manufacturing, and other sectors and pushing up unemployment. Weak growth and limited foreign exchange earnings have made public finances unsustainable, leaving authorities dependent on expensive borrowing for deficit finance and on Gulf allies to help cover the import bill. Egypt's current Constitution passed in a referendum that took place in January 2014.