The population of India in 2003 was estimated by the United Nations at 1,065,462,000, which makes it the second most populous country among the 193 nations of the world. China is the only nation with more people, and the only other country with more than one billion inhabitants. Moreover, the US Census Bureau expects India's population to surpass China's by 2035. The key to India's rapid population growth since the 1920s has been a sharp decline in the death rate because of improvements in health care, nutrition, and sanitation. In 1921, when India's population stood at 251,321,213, the birthrate was 48.1 but the
death rate was 47.2; by 1961, when the population reached 439,234,771, the birthrate was still high at 40.8, but the death rate had dropped by more than half to 22.8. A drop in the birthrate from 41.1 in 1971 to 30.2 in 1990–91, presumably attributable to an aggressive program of family planning, contraception, and sterilization, had little immediate impact on the compounded population growth rate, which averaged 2.1% in the 1980s and 1.9% in 1990–95. The government considers the rapid population growth a serious problem, particularly in relation to reducing poverty. The goal of the Indian government is to reach zero population growth by 2050 with a population of1.3 billion. In 2003 approximately 4% of the population was over 65 years of age, with another 36% of the population under 15 years of age. There were 106 males for every 100 females in the country in 2003. According to the UN, the annual population growth rate for 2000–2005 is 1.51%, with the projected population for the year 2015 at 1,246,351,000. The population density in 2002 was 319 per sq km (827 per sq mi). It was estimated by the Population Reference Bureau that 28% of the population lived in urban areas in 2001. The majority of people live in some 555,315 villages with fewer than 10,000 residents each.The capital city, New Delhi, had a population of 11,345,000 in 2002. Other large urban areas were Mumbai (formerly Bombay) (18,042,000), Calcutta (12,900,000), Delhi (11,680,000), Madras (6,639,000), Hyderabad (6,833,000), Bangalore (5,554,000), Ahmadabad (4,154,000), Pune (3,485,000), Kanpur (2,447,000), Lucknow (2,565,000), Surat 2,341,000), Nagpur (2,060.000), and Jaipur (2,143,000). According to the United Nations, the urban population growth rate for 2000–2005 was 2.8%. The surge in urban population is considered to be another major constraint to economic development.