Africa’s biggest economies are not undertaking major reforms to ease doing business fast enough.

The latest World Bank Doing Business report shows Nigeria and South Africa—the continent’s largest economies—have made meager progress over the past year. South Africa remains ranked 82nd out of 190 ranked countries while Nigeria fell one place to 146th, a reversal of fortunes after it recorded a 24-place rise in the rankings last year. As it typically does, the report measures the ease of doing business along ten various parameters including paying taxes, starting a business, enforcing contracts, registering property and getting credit.

In contrast however, smaller economies on the continent are recording big reform wins. Mauritius is a particular success story, rising five places to 20th—the only African country to make the top 20. Mauritius’ rise in the ranking is linked to consistent reforms over the years: since 2005, the time needed to register property has dropped more than 12-fold while time needed for business incorporation has also dropped nearly 10 times.