The price for oil produced by the Organization of the Petroleum Exporting Countries (OPEC) cleared the $44 mark on Monday, the Vienna-based cartel announced on Tuesday. One barrel (159 liters) of OPEC-produced crude stood at $44.14 at the start of the week, 0.99 dollars higher than last Friday. OPEC calculates a basket price based on 12 brands produced by its members, DPA reported.