The potato is a starchy, tuberous crop. It is the world's fourth-largest food crop, following rice, wheat and corn. The annual diet of an average global citizen in the first decade of the 21st century included about 33 kg (73 lb) of potato. The potato was first domesticated by the Andean civilizations in the region of modern-day southern Peru and extreme northwestern Bolivia between 8000 and 5000 BCE. It has since spread around the world and has become a staple crop in many countries. The following is a list of dishes that use potato as a main ingredient.