According to the ''Address-Based Population Recording System'' of Turkey, the country's population was 74.7 million people in 2011, nearly three-quarters of whom lived in towns and cities. According to the 2011 estimate, the population is increasing by 1.35 percent each year. Turkey has an average population density of 97 people per km². People within the 15–64 age group constitute 67.4 percent of the total population; the 0–14 age group corresponds to 25.3 percent; while senior citizens aged 65 years or older make up 7.3 percent.