Wealthy city-state Singapore has once again topped a ranking of the best places in the world to do business. The Economist Intelligence Unit (EIU) ranked Singapore as number one out of 82 countries for its "efficient [and] open economy". The tiny Asian island nation has been at the top of the rankings for seven consecutive years. Other countries ranked in the top five included Switzerland, Australia, Hong Kong and Sweden respectively. The rankings were based on the attractiveness of a country's business environment by looking criteria such as political climate, openness to foreign investment, taxes, the labor market and infrastructure. Last month, Singapore also topped the World Bank's ease of doing business report, which looked at 189 countries.