Formerly the British protectorate of Bechuanaland, Botswana adopted its new name upon independence in 1966. Four decades of uninterrupted civilian leadership, progressive social policies, and significant capital investment have created one of the most dynamic economies in Africa. Mineral extraction, principally diamond mining, dominates economic activity, though tourism is a growing sector due to the country's conservation practices and extensive nature preserves. Botswana has maintained one of the world's highest economic growth rates since it's independence, though growth slowed to 4.7% annually in 2006-07. Through fiscal discipline and sound management, Botswana has transformed itself from one of the poorest countries in the world to a middle-income country with a per capita GDP of nearly $15,000 in 2007. Two major investment services rank Botswana as the best credit risk in Africa. On the downside, the government must deal with high rates of unemployment and poverty. Unemployment officially was 23.8% in 2004, but unofficial estimates place it closer to 40%. HIV/AIDS infection rates are the second highest in the world and threaten Botswana's impressive economic gains. An expected leveling off in diamond mining production overshadows long-term prospects.