British influence and control over what would become Nigeria grew through the 19th century. A series of constitutions after World War II granted Nigeria greater autonomy; independence came in 1960. Oil-rich Nigeria, long hobbled by political instability, corruption, inadequate infrastructure, and poor macroeconomic management, is undertaking some reforms under a new reform-minded administration. Nigeria's former military rulers failed to diversify the economy away from its overdependence on the capital-intensive oil sector, which provides 20% of GDP, 95% of foreign exchange earnings, and about 65% of budgetary revenues. The largely subsistence agricultural sector has failed to keep up with rapid population growth - Nigeria is Africa's most populous country - and the country, once a large net exporter of food, now must import food. In November 2005, Abuja won Paris Club approval for a debt - relief deal that eliminated $18 billion of debt in exchange for $12 billion in payments - a total package worth $30 billion of Nigeria's total $37 billion external debt. The deal requires Nigeria to be subject to stringent IMF reviews. GDP rose strongly in 2006, based largely on increased oil exports and high global crude prices.