₹12,083 crore for January-March compared to a profit of ₹3,218 in the year-ago period. Even though revenue fell 15% year-on-year to ₹19,513 crore for the quarter, the massive quarterly net loss was attributed to a write-off of ₹17,132 crore on impairment of assets in oil and gas, copper and iron ore businesses.An asset is impaired, or its value written down in books of the company, when its projected future cash flows are lower than current carrying value.