SURVEY - Rwanda is the most improved sub-Saharan nation according to a survey looking at performances over the past five years. The Ibrahim Index, financed by Sudanese mobile phone magnate Mo Ibrahim, names Mauritius as the best-governed and Somalia as the worst-governed state. Harvard University academics analysed the criteria used to rank countries. They assembled data from various sources including the United Nations, the anti-corruption watchdog Transparency International, and thinktanks such as Freedom House. Countries are measured under categories like “Safety and Security” and “Human Development”. When these categories are put together an overall ranking is reached. Two island nations top the list of the best governed, Mauritius (Number 1) and Seychelles (2). Botswana, at Number 3, is a stable democracy that earns its money from diamonds and agriculture. Cape Verde (4) is a former Portuguese colony which survives economically from remittances by expatriate Cape Verdeans - there are said to be more Cape Verdeans in Boston, Massachusetts, than there are on the islands themselves! South Africa (5), Ghana (8) and Senegal (9) are all vibrant democracies that are proud to have politically well-informed populations. Seychelles is a luxury tourist destination. Worst-governed, according to the list - at Number 48 out of 48 - is Somalia, a country which has not had a functioning government since the overthrow of the dictator Siad Barre in 1991. The Mo Ibrahim Foundation is next month due to award over $5m - to the former African head of state who is judged to have demonstrated exemplary leadership. Agencies