An attempt to create the most comprehensive annual benchmarks to measure the performance of governments in Africa shows the Indian Ocean island of Mauritius to be the best-governed country in Africa, Somalia the worst, and Rwanda the fastest improving.

The Ibrahim Index of African Governance was published on Tuesday in London by Mo Ibrahim, a Sudanese-born former telecommunications magnate turned philanthropist. It sets out to provide a more complete picture of governance in Africa than existing indices, in the hope of providing “objective criteria by which citizens can hold their governments to account” and to stimulate African leaders to improve.