The Institute of Statistics (INSTAT) estimated the population of the municipality of Tirana at 418,495 in 2011. With a population density of 502 people per square kilometre, Tirana is the most densely populated municipality in the country. The encompassing metropolitan area, consisting of the regions of Durrës and Tirana, has a combined population of approximately 1 million amounting to nearly one third of the country's total population.