Oil prices boosted by global output reductions will be capped because of new supply before long, according to Goldman Sachs Group Inc. The cuts by OPEC members and nations outside the group, as well as strong demand growth, will probably help curb inventories by next summer, analysts including Damien Courvalin said in a note dated Dec. 16. While the bank raised its oil-price forecasts for the second quarter of 2017, it decreased its crude estimates for 2018 on concern that new production will enter the market. Brent crude, the benchmark for more than half of the world’s oil, has surged since the Organization of Petroleum Exporting Countries agreed Nov. 30 to trim output for the first time in eight years.