OMAHA, Neb. — Warren Buffett's company reported an 87 percent jump in its second-quarter profit as the paper value of its investment portfolio increased with the stock market, but it took a roughly $10 billion write-down on the value of its aircraft parts manufacturing business because of the economic impact of the coronavirus pandemic.

Berkshire Hathaway said Saturday that it earned $26.3 billion, or $16,314 per Class A share, during the second quarter. That's up from $14.1 billion, or $8,608 per share, a year ago.

Berkshire said it cut the value of its Precision Castparts unit because of how much the pandemic has hurt air travel and businesses that support that airline industry. Precision Castparts cut about 10,000 jobs, or about 30 percent of its workforce, during the first half of the year as it responded to the reduced demand.

CFRA analyst Cathy Seifert said the Precision Castparts write-down — combined with Berkshire's sale of all its airline stocks earlier this year — suggests that Buffett expects the pandemic to have a lasting negative impact on the airline business.