Ranked number one in Africa on Transparency International's anti-corruption index, Botswana is a stable democratic country which has historically enjoyed among the highest economic growth rates in the world. Botswana's ranking on the 2013 World Bank/IFC Doing Business report was 59 out of 183 countries globally. Its score compared favorably to all other African countries except Rwanda (52) South Africa (ranked 39) and Mauritius (ranked 19). Botswana has a stable, A2 credit rating, the highest in Africa. Botswana's mining industry dominates the economy: Preliminary estimates indicate that mining contributed 21% of overall GDP in 2012 and contributed about a third of the government's total revenue. Despite mining's great contribution to the country's wealth, the sector only accounts for about 5% of employment. Botswana's economy is among the most skewed in the world between rich and poor, and an estimated one fifth of Botswana's population survives on less than $1.25/day. Largely due to diamond revenue, Botswana enjoyed the highest GDP growth rate in the world from 1970 to 1999 (8.3%). Its economy contracted in the wake of the global financial crisis and has not fully recovered. Real GDP grew by 3.7% in 2012 and is expected to grow between 4 to 6% in 2013. The non-mineral GDP growth rate for 2012 is estimated to be 11.6%. Botswana's mining revenue has provided the government with resources to construct and maintain a historically solid infrastructure, including roads, telecommunication systems, hospitals, hotels, and schools. While the presence of a well-maintained infrastructure, complimented by political stability, has tended to encourage foreign investment, poor planning and workmanship has caused several infrastructure problems, particularly in the power and water sectors, that are likely to act as a brake on growth during the next 12-24 months.