Convert from hectare meter to drum [metric, petroleum]

Unit Definition (hectare meter)
The hectare meter is a unit of volume used to measure the capacity of reservoirs, equal to the volume of water one meter deep covering one hectare. The unit is used mostly in British Commonwealth countries, especially India, where it provides a metric unit comparable to the traditional English acre foot. Reservoir capacities are often stated in millions of hectare meters (Mha·m or MHM). One hectare meter equals exactly 10 000 cubic meters or about 8.1071 acre feet.

Unit Definition (drum [metric, petroleum])
The drum [metric, petroleum] is a unit of volume sometimes used in the oil trade. In the metric world, drums of 200 liters, 205 liters, and 208 liters are in use as substitutes for the traditional size.