Colombian coal miner Cerrejon’s production and export levels fell in 2020 due to lower demand, price declines, the impact of the coronavirus pandemic, and a three-month strike that paralyzed operations, as reported by Reuters.

The miner produced 12.4 million metric tons (mt) of coal in 2020, down almost 52% from the 25.8 million mt it produced in 2019. Exports fell 48.2% from 26.3 million mt in 2019 to 13.6 million mt in 2020, the lowest level in the last 18 years.

Last year was “one of the most difficult in Cerrejon’s history,” the company said in a statement, citing reduced activities during a 40-day period while it established biosecurity measures, and the 91-day strike, its longest ever, among other reasons.

The company is owned equally by BHP Group, Anglo American and Glencore.