The oil supply summary monthly report provides analysis on short-term global oil supply through 2018. The written document is accompanied by a related excel data download. Global supply growth in 2017 has been revised up this month but remains weak, at 240,000 b/d year-on-year. This follows growth in 2016 of only 200,000 b/d – a step change from the annual average increases of two million b/d between 2010 and 2015. Underpinning a second year of weak supply growth is the assumption that OPEC and Russia will rollover the agreed supply cuts into the second half of 2017, and that adherence will remain strong. However, the key question for 2018 supply is the return of OPEC and Russian production, which we assume occurs from the end of 2017. A full return would result in a strong surge in supply, with output rising by 2.4 million b/d in 2018.