Speaking at Berkshire’s annual shareholder meeting in Omaha, Buffett also said overall first-quarter operating profit probably fell 12% to $3.73 billion from $4.24 billion a year earlier.

Buffett said the BNSF railroad was hurt by declining oil prices and coal shipments while insurance underwriting was hurt by loss claims related to hailstorms.

“Railroad carloading throughout the industry—all of the major railroads—were down significantly in the first quarter, and probably almost certainly will continue to be down for the balance of the year,” Buffett said.

Preliminary profit at the Omaha-based insurance and investment conglomerate rose about 8% to $5.59 billion, helped by a gain from the swap of Procter & Gamble (PG) stock for the Duracell battery business. Final results are due on May 6.

Berkshire owns close to 90 businesses in energy, insurance, manufacturing, railroad, retail and other sectors, and invests well over $100 billion in stocks.

At the meeting, Buffett and Berkshire Vice Chairman Charlie Munger fielded questions from shareholders, analysts, and journalists, primarily about Berkshire companies and investments.

Buffett parried concerns raised by a shareholder, and previously by hedge fund manager William Ackman, that Berkshire’s roughly 9 percent stake in Coca-Cola promotes health problems by selling its sugary drinks.

Buffett, who consumes 700 calories of Coke a day, said it seemed wrong to blame calories alone for rising obesity levels.

“I elect to get my 2,600 or 2,700 calories a day from things that me feel good when I eat them,” he said. “That’s my sole test.”

Buffett also said he was comfortable with Berkshire’s big stakes in Wells Fargo (WFC) and, through in-the-money warrants, Bank of America Corp, but he warned about the risk that derivatives pose for most of the world’s biggest banks, especially if markets were disrupted.

“It is still a potential time bomb,” he said, but added that “I’m not in the least troubled by our investment in Bank of America…. Or Wells Fargo.”

Buffett also lavished praise on Mark Donegan, chief executive of Precision Castparts, which Berkshire bought in January for $32 billion, its largest purchase. He also said Precision will do better under Berkshire than it did independently because it can tap Berkshire’s capital base.

“Mark Donegan is an extraordinary manager. I would almost rank Mark as one of a kind,” Buffett said, before joking: “If he needs capital, he’s got my 800 number.”

The meeting attracted people from around the world, including hundreds who waited hours in a rainstorm before doors opened at 6:20 a.m., 40 minutes early.

“I wanted to make sure I got a good seat,” said Kim Baumler, an office manager for a wealth management company from Fargo, North Dakota, who said she was at the head of the line at 10:30 p.m. Friday night. “My boss is a huge Warren Buffett follower, and I got hooked. I wanted to see what it was all about.”