(Bloomberg) Reduced spending by oil explorers will lead to a global shortage of crude within the next few years, according to industry consultant Rystad Energy.

While the world’s exploration and production companies need to replace 34 billion barrels of oil every year to meet consumption needs, the companies made investment decisions that will result in only about 8 billion barrels in 2015, Rystad said in a report released Wednesday.

Exploration and production spending around the world fell by $250 billion this year and is expected to drop another $70 billion in 2016, according to the report. Those spending cuts are reducing the profits of the world’s largest oil services companies. Halliburton Co. said Wednesday at the Wells Fargo energy conference in New York that margins outside the U.S. and Canada are expected to be lower next year.