Half of the world's 2,000 biggest listed companies have set a target to get to net-zero emissions by the middle of the century, but just a fraction meet tough United Nations guidelines for what constitutes a quality pledge, a report on Monday showed.

Net Zero Tracker, an independent data consortium including Oxford University, said corporate targets from Forbes2000 index companies had jumped 40% to 1,003 in October 2023, from 702 in June 2022, covering two-thirds of revenues, some $27 trillion.

However, just 4% of the targets meet the criteria laid down by the U.N.'s Race to Zero campaign, for example by covering all emissions, starting to cut them immediately, and including an annual progress update on interim and longer term targets.