Explanation:

Page 74, Economic Survey Volume 1 2015-16: This section discusses the pattern of India’s food trade with reference to the export of water “embedded” in these foodstuffs (this does not take into account water used in production).

India was a “net importer” of water until around 1980s. With increases in food grain exports, India has now become a net exporter of water – about 1 per cent of total available water every year.
The ratio of export to import of such virtual water is about 4 for India and 0.1 for China.
The global market for foodstuffs is depleting water sources in many parts of the world quicker than they can naturally be refilled. The complex trade is increasing pressure on non-renewable groundwater, mainly used for irrigating crops such as rice, wheat and cotton.
Pakistan, the US and India are the countries exporting the most food grown with unsustainable water.