 Throughout most of the twentieth century Mexico's population was characterized by rapid growth.Although this tendency has been reversed and average annual population growth over the last five years was less than 1%, the demographic transition is still in progress, and Mexico still has a large cohort of youths.The most populous city in the country is the capital, Mexico City, with a population of 8.9 million (2016), and its metropolitan area is also the most populated with 20.1 million (2010).