The Energy Information Administration's (EIA) Natural Gas Storage Change Index is published weekly based on gas volumes available in underground storage facilities. The indicator demonstrates whether withdrawals or injections were prevailing in the past week in the US. The indicator allows measuring the US demand for natural gas.
Although this is a US indicator, it indirectly affects the Canadian dollar (CAD), since Canada's raw material economy largely depends on US demand for gas.
An increase in natural gas inventories is an indication of a weaker demand for gas.