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
What It Is. Profit margin usually refers to the percentage of revenue remaining after all costs, depreciation, interest, taxes, and other expenses have been deducted. The formula is: Note that preferred stock dividends are typically included in the calculation, but common stock dividends are not.