Warren Buffett may be the first CEO to talk about how recently passed tax cuts have helped his company—Berkshire Hathaway—amass more wealth.

The tax cuts will reduce the tax rate for many U.S. corporations to about 21%, about half the previous rate.

In his annual letter to shareholders, which serves as a preface to Berkshire’s annual report, Buffett said his company received a $29 billion windfall from the new tax legislation.

That’s not all, Buffett—one of the most famous and wealthiest investors in the world, worth an estimated $87 billion—had some critical words for bonds, and suggested Berkshire might make a big acquisition this year.

Berkshire benefits from tax cuts, big time

Buffett said the net worth of Berkshire increased $65 billion in 2017. But nearly half of the gain came from the tax cut:

“A large portion of our gain did not come from anything we accomplished at Berkshire,” Buffett writes. “The $65 billion gain is nonetheless real – rest assured of that. But only $36 billion came from Berkshire’s operations. The remaining $29 billion was delivered to us in December when Congress rewrote the U.S. Tax Code.”

For the year, Berkshire reported profit of $45 billion, nearly double its earnings for 2016.

(Not) betting on bonds

Buffett also said investors could be better off in stocks, rather than bonds:

“It is a terrible mistake for investors with long-term horizons—among them, pension funds, college endowments, and savings-minded individuals—to measure their investment ‘risk’ by their portfolio’s ratio of bonds to stocks,” Buffett said. “Often, high-grade bonds in an investment portfolio increase its risk.”

Why did he say that?

In 2007, as part of a wager with a hedge fund called Protege, Berkshire purchased $500,000 of U.S. Treasuries, usually the safest bonds investors can buy because they are backed by the U.S. government. At one point, they yielded a scant 0.88%, which didn’t keep pace with 1% inflation at the time, Buffett said.

“Given that pathetic return, our bonds had become a dumb—a really dumb—investment compared to American equities,” Buffett writes, adding that an investment in an index following S & P 500 companies would have earned more than 10%.

Buffett also said investors could be better off in stocks, rather than bonds

Not everyone agrees with Buffett’s bond bashing. Morgan Stanley recently said in a written report that a sell-off in Treasuries that began in September has ended and now bonds with longer maturities could be a good bet.

Berkshire’s next buys

Berkshire has amassed a stockpile of about $116 billion in uncommitted cash. Buffett said that in order to achieve the double digit growth the company has experienced in recent years, Berkshire will have to purchase some large businesses in 2018.

“Berkshire’s goal is to substantially increase the earnings of its non-insurance group,” Berkshire wrote. “For that to happen, we will need to make one or more huge acquisitions. We certainly have the resources to do so.”

What might the company buy? General Electric and Southwest Airlines are two bets some industry experts have made.

Good to know: It may be 2018, but numerous public companies are just wrapping up their financial reports for 2017, which they must file with the Securities and Exchange Commission (SEC).  An annual report, as its name suggests, documents a company’s financial performance for the year.

More About Buffett and Berkshire

Buffett—known as the Oracle of Omaha, because he’s headquartered in Omaha, Nebraska and has made smart stock picks over a 50+-year career– built Berkshire Hathaway, from a small cloth mill and manufacturer in New England, to a multi-billion dollar enterprise whose stock has increased by 1.8 million percent since the 1960s.

Buffett is famed for betting on slow-growing companies that increase in value over time.

Berkshire Hathaway is what’s known as a conglomerate. That means it owns numerous companies under one umbrella. In fact, it owns 63 companies, some of which are among the most recognized brands in the U.S., including battery maker Duracell, and underwear manufacturer Fruit of the Loom. It also owns paint company Benjamin Moore, and the confectioner See’s Candies. It also owns a sizable stake in the traditional insurance business, as well as auto insurer Geico.

Additionally, Berkshire owns sizable stakes in major U.S. companies including American Express, Apple, and Coca-Cola.

Berkshire Hathaway is a public company with two classes of shares: Class A shares and Class B shares. Class A shares are for generally for institutional investors, and Class B shares are for individual investors.

The future of Berkshire

Buffett recently made two important promotions at Berkshire. Buffett is 87, and his business partner Charlie Munger is 94. Speculation had swirled for years about who might replace them to run the company. In January,  Buffett made Gregory Abel, 55, vice chair of the company’s non-insurance businesses, according to a company press release. Abel headed up Berkshire Hathaway Energy.

He also advanced Ajit Jain, 66, to be vice chair of the company’s insurance group. Jain was the executive vice president of Berkshire’s National Indemnity Company.