Помогите, пожалуйста, разобраться, в чем разница между терминами oil stocks, oil inventories и oil stockpiles и каким терминам они соответствуют в русском языке?

контекст:
OECD commercial stocks declined counter-seasonally by 3.1 mb month-on-month (m-o-m) in April to 2 809 mb, reaching a new three-year low. Inventories have fallen in eight of the last nine months. OECD crude and oil products both drew moderately, whereas NGL holdings increased. Higher refinery throughput in Asia Oceania helped reduce crude holdings, while strong demand for middle distillates in Europe and the Americas triggered a counter-seasonal draw. At end-month, OECD stocks were 27 mb below the five-year average, with crude and oil products both in deficit. OECD inventories may only take a few months to fall to the ten-year average, as the excess was just 55 mb at the end of April.

мои варианты:
stocks = товарные запасы (вся добытая нефть, за исключением стратегического резерва)
inventories = stockpiles = складские запасы (нефть в хранилищах)

Заранее спасибо!

(я не специалист, могу ошибаться в точности русских названий)