The roots of its modern existence trace back to the British Indian Army that ceased to exist following the Partition of British India, resulting in the parliamentary act that established the independence of Pakistan (as the Dominion of Pakistan) from the United Kingdom on 14 August 1947.[7]:1–2 According to statistics provided by the International Institute for Strategic Studies (IISS) in 2020, the Pakistan Army has approximately 560,000 active-duty personnel, supported by the Army Reserve and National Guard[8][9]—effectively making it the 6th largest army in the world in terms of manpower.[10][11] Pakistani citizens can enlist for voluntary military service upon reaching 16 years of age, but cannot be deployed for combat until age 18 in accordance with the Constitution of Pakistan.[12]