Global insured losses tied to natural catastrophes in the first half of 2017 totaled an estimated $22.0 billion, with just over three-quarters of the cost attributable to the United States, Impact Forecasting, the catastrophe modeling unit of Aon Benfield, said in a report released Wednesday.

However, the estimate is 35% below the 10-year average of $34 billion and 12% below the 17-year average of $25 billion, according to the report, “Global Catastrophe Recap: First Half of 2017.”

The U.S. had 76% of the global losses sustained by public and private insurance entities during the first half of 2017, the report said. Europe, the Middle East and Africa and the Asia-Pacific region each accounted for 10%.

Impact Forecasting estimates that 42% of first-half 2017 global economic losses were covered by insurance, above the near- and medium-term average of 32%, largely because the majority of losses occurred in the U.S., the report said.

Economic losses from natural disasters during the first half of 2017 totaled an estimated at $53 billion globally, 56% lower than the 10-year average of $122 billion and 39% below the 17-year average of $87 billion, the report said.

Severe convective storms caused the bulk of both insured and economic losses, responsible for some $17 billion of insured losses, or 78% of the total, with roughly $16 billion tied to hail, straight-line winds and tornadoes. Severe storms also caused $26 billion in economic loss, or 48% of the total, according to the report.

Mortality was also down in the first half of 2017 as natural disasters caused 2,782 fatalities, the least since 1986, according to the report, and a fraction of the long-term average from 1980 to 2016 of 40,867 lives. Flooding caused the greatest toll at with at least 1,806 deaths.

“The financial toll from natural catastrophe events during the first six months of 2017 may not have been historic, but it was enough to lead to challenges for governments and the insurance industry around the world,” Steve Bowen, Impact Forecasting director and meteorologist, said in a statement. “This was especially true in the United States after the insurance industry faced its second-costliest first half on record following a relentless six months of hail-driven severe weather damage.”