Revenue and Coinage :Around the 5th century BC Punch marked silver ingots in circulation and the first metallic coins were minted around the 6th cecentury BC by the Mahajanapadas of the Gangetic plains, the earliest traces of coinage in India.While India's many kingdoms and rulers issued coins, barter was still widely prevalent . Villages paid a portion of their agricultural produce as revenue while its craftsmen received a stipend out of the crops at harvest time for their services. Each village, as an economic unit, was mostly self-sufficient.
Exports :Surplus of Indian manufactures, like the muslin of Dacca,Calicos of Bengal, Shawls of Kashmir, steel and iron works, silk, and other textiles and handicrafts, agricultural products like pepper, cinnamon, opium, and indigo were exported to Europe, the Middle East and South-East Asia in return for gold and silver. GDP estimate : According to economic historian Angus Maddison in his book The World Economy: A millinnial Perspective , India had the world's largest economy from the first to 11th century, and in the 18th century, with a 32.9% share of world's GDP in the 1st century to 28.9% in 1000AD, and in 1700 AD with 24.4%.