"A large portion of our gain did not come from anything we accomplished at Berkshire", Buffett wrote.
Buffett learned that so-called "risk-free" bonds were a "far riskier" investment than a long-term investment in common stocks.
Buffett got a $29 billion boost to net earnings in the fourth quarter from the tax code changes.
The company's often-impressive pace of acquisitions had slowed a year ago, he noted, when the prices asked for businesses 'hit an all-time high, ' amid what he called 'a purchasing frenzy'.
Buffett bemoans the acquisition frenzy on Wall Street that's been fueled by extraordinarily cheap debt, making it hard to find possible acquisitions at a "sensible purchase price".
Microsoft Surface Pro 2017 launches in India for Rs 64999
It also has a hinge that lets users adjust the tablet by up to 165 degrees, letting them operate the Surface Pro in Studio Mode. Microsoft has announced availability of new Surface Pro in India which was unveiled in the month of May past year .
It was also short on faulting excesses of Wall Street and Washington, and said nothing about Berkshire's plan to create a healthcare company with Amazon.com Inc and JPMorgan Chase & Co.
Buffett had a mixed reaction to the tax overhaul passed by Congress previous year. "Buffett doesn't dwell very long on the politics", Smead said.
Amateur investors who put their money in low-priced index funds can beat the so-called "smart money" hedge funds charging extraordinary management and performance fees.
All told, the S&P 500 had an overall gain of 125.8% while the group of hedge funds - which have never been publicly named - gained just 27%.
As for other Berkshire operations, Buffett this year is refraining from going through them on an individual basis.
Li Shufu-owned Geely Group becomes largest shareholder in Daimler AG
The size of the investment leapfrogs a 6.8% stake in the Stuttgart-based group held by Kuwait and Renault-Nissan's 3.1% holding. Daimler is the world's oldest automaker, with brands including Mercedes-Benz and Smart cars, as well as heavy trucks.
Buffett supported Hillary Clinton, a Democrat, in the 2016 USA presidential election.
Buffett, 87, also avoided dropping any hints about who will take the reins at Berkshire when he retires.
Buffett declared in his 2015 annual shareholder letter that he has found the "right person", but he didn't offer any further details.
Last month, he gave two top executives Ajit Jain and Gregory Abel greater oversight of Berkshire's operating businesses, cementing their status as the front runners to succeed Buffett atop the conglomerate. Kraft Heinz Co said yesterday billionaire investor Warren Buffett has chose to retire from the company's board following the end of his term in April to reduce travel commitments.
Warren Buffett said in his annual letter the practice of managing portfolio risk using a specified ratio of bonds-to-stocks is flawed.
Jimmy Butler challenges Lou Williams to 1-on-1 for $100K
An All-Star, Butler is averaging 22.4 points, 5.5 rebounds and 5.0 assists in his first season with the Wolves. The Rockets' hot streak continues as they sit atop the Western Conference with the best record in the league.
The investor shared the data which revealed Berkshire Hathaway's stock declined by a range of 37 percent to 59 percent multiple times over the last five decades.