第二项金融投资是50亿美元购入美国银行（Bank of America）优先股，附带期权允许伯克希尔在2021年9月2日前以每股7.14美元的价格购买7亿股普通股。美国银行当前股价约8美元/股。巴菲特对这项投资的评价是“我们的期权在到期前有望达到极高的价值”。

    至于第三项投资，巴菲特能说的只有抱歉。在公开信中，他承认几年前自己投资约20亿美元，买入公用事业公司Energy Future Holdings（在被KKR等私有化前，前身是TXU）的几只高收益率债券，完全是个错误。假如这几年天然气价格上涨，EFH有机会在火电厂项目上大赚一笔，投资它的债券也会不赖。但事实上，气价急剧下降，EFH也陷入了财务危机。

    伯克希尔2010年将EFH投资减记10亿美元，2011年再次减记3.90亿美元。巴菲特并不讳言自己在这项投资上判断失误：“不管事情最终将怎样变化，我当初买入债券时完全算错了盈亏概率。用网球比赛的行话来说，这是我作为董事长犯下的一个非受迫性失误。”

    本文作者是《财富》杂志的资深特约编辑卡罗尔•卢米斯，她是沃伦•巴菲特的老朋友，也是伯克希尔哈撒韦的股东。她已经连续35年义务担任沃伦•巴菲特致股东公开信的编辑。

    A second financial investment was $5 billion of preferred stock in Bank of America (BAC) that came with warrants allowing Berkshire to buy 700 million common shares at $7.14 per share anytime before September 2, 2021. Bank of America stock is currently selling at about $8 per share. Says Buffett of this investment: "Our warrants will likely be of great value before they expire."

    Of the third Berkshire investment, Buffett has absolutely nothing good to say. In his letter, he concedes that he completely blew things a few years ago by putting around $2 billion into several high-yield bond issues of utility operation Energy Future Holdings (which in its former life, before it was taken private by KKR and others, was called TXU). Had the price of natural gas risen and given EFH an opportunity to make good money off its coal-burning plants, the company's bonds would have been golden. Instead, the price of natural gas has nosedived and turned EFH into a financial disaster.

    Berkshire wrote down its EFH investment by $1 billion in 2010 and by another $390 million in 2011. Buffett is blunt in assessing his judgment in this matter: "However things turn out, I totally miscalculated the gain/loss probabilities when I purchased the bonds. In tennis parlance, this was a major unforced error by your chairman."

    The writer of this article, FORTUNE senior editor-at-large Carol Loomis, is a longtime friend of Warren Buffett's and a shareholder of Berkshire Hathaway. She has been the pro bono editor of Buffett's annual letter to shareholders for 35 years.