According to a report released by a UN-backed panel Monday, the Earth’s ozone layer is healing at a pace that would see it fully mended in less than 50 years. The report found the ozone layer is expected to fully recover across most of the world by 2040, over the Arctic by 2045, and over the Antarctic by 2066.

“Variations in the size of the Antarctic ozone hole, particularly between 2019 and 2021, were driven largely by meteorological conditions,” the UN’s World Meteorological Organization (WMO) said Monday. “Nevertheless, the Antarctic ozone hole has been slowly improving in area and depth since the year 2000.”

According to Paul Newman, co-chair of the report and chief Earth scientist at NASA’s Goddard Space Flight Center, chlorine and bromine are the two chief chemicals that munch away at the ozone layer. As evidence of the ozone layer healing, the report found chlorine levels are down 11.5% since they peaked in 1993. Bromine levels have dropped 14.5% since their 1999 peak.

The report, published every four years, takes a look at the long-term effects of the Montreal Protocol, a global agreement adopted in 1987 to protect the Earth’s ozone layer by phasing out the chemicals that deplete it. According the WMO, Monday’s report “confirms the phase out of nearly 99% of banned ozone-depleting substances has succeeded in safeguarding the ozone layer, leading to notable recovery of the ozone layer in the upper stratosphere and decreased human exposure to harmful ultraviolet (UV) rays from the sun.”

“The impact the Montreal Protocol has had on climate change mitigation cannot be overstressed,” Meg Seki, Executive Secretary of the United Nations Environment Programme’s Ozone Secretariat, said in a statement. “Over the last 35 years, the Protocol has become a true champion for the environment.”

The Associated Press contributed to this report.