Karachi is Pakistan’s largest city and its only international port. It has a population of 8.2 million, which means that 6 percent of the total and 22 percent of the urban population of the country live in this city. Its rate of growth is 5.6 percent per year, 3 percent due to natural growth, and 2 to 3 percent due to migration from other parts of the country. This is much higher than the 3.2 percent growth rate for the whole of Pakistan. Karachi provides 25 percent of the federal revenues and 15 percent of the gross domestic product of Pakistan. In addition, 50 percent of the country’s bank deposits and 72 percent of all issued capital is from Karachi. The anarchic conditions in northern India in the 18th century made the traditional trade routes from India to Central Asia unsafe. Thus, goods were sent to Karachi by sea from the Indian peninsula, and then overland through Baluchistan and Kabul to Herat, Samarkand, and Bukhara. Due to this Central Asian trade, Karachi became an important port and its merchants expanded their zone of operations as far as China in the east, Zanzibar in the south, and Kyiv in the west. The Russian expansion towards the Arabian Sea in the early 19th century threatened British interests in the region, and so, in 1839, the British occupied Karachi and used it for landing troops and armor for their Afghanistan campaigns to contain the Russians. In 1843, they annexed the kingdom of Sindh to their empire and made Karachi the administrative center of Sindh.