Zambia has been inhabited for thousands of years by hunter-gatherers and migrating tribes. On October 24th, 1964, the protectorate gained independence with the new name of Zambia, derived from the Zambezi river which flows through the country. Despite progress in privatization and budgetary reform, Zambia's economic growth in 2005-06 remained somewhat below the 6-7% per year needed to reduce poverty significantly. Privatization of government-owned copper mines relieved the government from covering mammoth losses generated by the industry and greatly improved the chances for copper mining to return to profitability and spur economic growth. Copper output has increased steadily since 2004, due to higher copper prices and the opening of new mines. The maize harvest was good again in 2005, helping to boost GDP and agricultural exports. Cooperation continues with international bodies on programs to reduce poverty, including a new lending arrangement with the IMF in the second quarter of 2004. A tighter monetary policy will help cut inflation, but Zambia still has a serious problem with high public debt.