(Reuters) — Berkshire Hathaway Inc., the conglomerate run by Warren Buffett, may see its book value grow by $37 billion because of U.S. tax law changes enacted by President Donald Trump, Barclays Capital analysts estimated on Monday.

Book value, a key performance measure for Mr. Buffett reflecting assets minus liabilities, probably rose by 12% in the final quarter of 2017 because Berkshire can lower its tax bill on investments that have risen in value, Barclays analysts led by Jay Gelb wrote.

That would leave Berkshire valued at about 1.39 times book value, which Mr. Gelb called "attractive," though it would remain above the 1.2 ratio that could prompt Mr. Buffett to authorize share repurchases.

Berkshire has said it ended September with $86.6 billion of income tax liabilities, which were mainly deferred.

Mr. Gelb, who rates Berkshire "overweight," also said lower taxes could boost by 12% the earnings power from Berkshire's more than 90 operating units, such as the BNSF railroad and Geico auto insurance.

Though the tax changes would not add to the Omaha, Nebraska-based company's roughly $109 billion of cash and equivalents, Mr. Gelb said any large all-cash acquisition would likely immediately boost Berkshire's earnings per share.

President Trump last month signed into law a reduction in the corporate income tax rate to 21% from 35%.

Mr. Buffett had told CNBC in October that if the corporate rate changed significantly in 2018, "it would pay me something."

Through 2016, Berkshire's book value per share grew at an annualized 19% since Mr. Buffett took over the company in 1965. That topped the 9.7% annualized gain in the Standard & Poor's 500 including dividends. Berkshire does not pay a dividend.

Barclays on Monday also raised its price target for Berkshire Class A shares to $357,000 from $322,500, three weeks after the shares reached $300,000 for the first time. It raised its target for Berkshire Class B shares to $238 from $215.

Berkshire usually releases yearend results and Mr. Buffett's annual shareholder letter on the last Saturday in February.

In afternoon trading, Berkshire Class A shares were up $1,575 at $303,100, and Class B shares were up 64 cents at $202.06. Both share classes rose 22% in 2017.