Scharfsinn/Shutterstock Oil production by the 18 members with monthly targets fell in March by 120,000 barrels per day to 34.11 million barrels per day. Kazakhstan was again the main overproducer by a wide margin.Overall, crude output by the 22-member group declined by 360,000 b/d to 40.92 million b/d, as production by all four members without a target fell. Save for later Print Download Share Last month’s crude oil production by Opec-plus fell by 360,000 b/d to 40.94 million b/d, the biggest monthly drop in six months, led by declines in Libya and Iraq, ʶԳ’s preliminary assessment shows.