The beginning of the amazing events at Krakatoa in 1883 date to May 20 when there were initial rumblings and venting from the volcano, which had been dormant for about 200 years.
A refinery margin is the revenue associated with refining petroleum, expressed as a value per volume (e.g. $/L), net of the cost of the crude oil input. The simplest refining
Nonetheless, a comparison of refining margins between regions and over time provides a good indication of the relative profitability of refining in a given market: If the margin is rising, it generally means profits are rising; Similarly, if the margin in one region rises much more rapidly than in other regions,