The reason is that the costs of extracting oil and gas are based on a devalued ruble, which makes them low for producers such as the state-run Rosneft and Gazprom, respectively. But the two companies products are sold on the world market for dollars, not rubles, making their profit margins higher, according to a Wood Mackenzie analysispublished July 17.
The average global price of oil began dropping in the early summer of 2014, plunging from more than $100 per barrel in June to below $50 early this year. At that time, the value of the ruble plunged 41 percent against the dollar as a result of the drop in oil prices and the sanctions imposed by Western countries on Russia because of its role in the Ukraine unrest .... http://uk.businessinsider.com