Cargill Inc said on Thursday that quarterly earnings fell 82 percent, the giant U.S. agribusiness firm’s worst quarter in more than 20 years, hurt by volatile commodity markets and weak margins in key areas like beef and oilseeds.

The results, the third weak quarter in the last four, were for the three months ending in May, before the worst drought in half a century starting battering grain crops and herds in the U.S. Plains and Midwest. So more challenges lie ahead with the drought, Cargill’s chief financial officer told Reuters.

“It is a significant disruption,” said CFO Sergio Rial in an interview. “It will put pressure on U.S. grain exports.”

Cargill’s smaller rivals like Archer Daniels Midland and Bunge have seen similar pressures, reporting disappointing earnings for the quarter ended June 30.

More from Reuters