The population of Pune has grown over five times in the last 50 years to approximately 25 lakhs according to the 2001 Census. Pune has a relatively young population, with 62% under the age of 30 and a median age close to India's average of 24 years. Approximately 50% of Pune's population growth is due to in-migration. The population is projected to reach 56.57 lakhs by 2031, which would result in a population density over 23,000 per square kilometer. Key issues arising from this growth include increased demand for housing and stress on public transportation without proper planning.