Peabody Energy writes down value of world's largest coal mine by $1.42 billion

• The move came as Peabody posted an overall second-quarter loss of $1.54 billion.

The big picture: The write-down was the result of "changes in multiple assumptions, including lower long-term natural gas prices, timing of coal plant retirements and continued growth from renewable generation," the company said.

• Coal's share of the U.S. electricity mix has been declining for years, and the country's coal production last year hit its lowest level since 1978, with continued declines occurring this year.

What they're saying: The pandemic is adding to the sector's woes, Moody's analyst Benjamin Nelson tells the Financial Times.

• “The longer the pandemic plays out, the more early retirements [of coal-fired plants] and permanent demand destruction from coal we’ll see,” Nelson said.