伯克希尔哈撒韦（Berkshire Hathaway）上周六公布，2011年每股账面价值增长了4.6%——这样的增幅虽不算大，但对于公司董事长沃伦•巴菲特而言已经够了，因为他已经达到了每年超越标准普尔500指数总回报率的目标。2011年标准普尔500指数仅上涨了2.1%。

    这是巴菲特掌管伯克希尔哈撒韦47年来公司每股账面价值增幅跑赢标准普尔500指数的第39个年头。

    尽管如此，在这第四十七年，巴菲特长期以来保持的一项骄人纪录却画上了句号。此前，公司每股账面价值平均年增长超过20%，但今年增幅只有19.8%，首次跌至20%以下。

    巴菲特当然也想让每股账面价值的增幅保持在20%以上，但这么多年来，他知道这个纪录终有结束的一天。他曾多次警告伯克希尔的股东们，公司庞大的资本基础将不可避免地放缓每股账面价值的增长。截至2011年底，公司的资本基础已经高达1,650亿美元。

    巴菲特在向股东汇报业绩时通常采用每股账面价值，因为这一方法能反映伯克希尔已实现和未实现的所有资本损益。由于伯克希尔持有庞大的普通股组合（截至年底770亿美元），并积累了巨大的未实现收益，它们的变动对业绩影响重大。

    若采用最常见的会计标准（不反映未实现利润，只反映未实现损失），2011年伯克希尔A类股每股收益6,215美元，低于2010年的7,928美元。

    净利润下降（以及每股账面价值增幅相对温和）的一个重要原因是2011年伯克希尔核心的保险业务经历了困难的一年。巨灾险损失高达26亿美元，而且定价不高。

    总体而言，伯克希尔的保险业务2011年仅实现保险利润2.48亿美元，远远低于2010年，当时的数字略高于20亿美元。保单额庞大的再保险业务在新西兰和日本地震中损失高达8亿美元，2011年亏损了7.14亿美元。

    但在致股东的公开信中，巴菲特重点关注的不是这一年的利润水平，而是2011年是伯克希尔保险业务连续第九年实现保险利润。与之形成鲜明对比的是保险界大部分公司都出现了保险损失。

    在伯克希尔实现保险利润的九年里，公司“浮存金”（即不属于伯克希尔，但可用于投资并享受收益的资金）已从410亿美元增至700亿美元。巴菲特在致股东的公开信中称，他预计浮存金在这个基础上不会出现太大的增长，因为这一数额与伯克希尔的保费收入相比已经显得特别庞大。

    Berkshire Hathaway reported today that its book value per share rose 4.6% in 2011—hardly a mighty leap but enough for the company's chairman, Warren Buffett, to meet his annual goal of beating the total return of the S&P 500 index, which rose only 2.1%.

    That was the 39th year out of the 47 years in which Buffett has run Berkshire that the company's performance was better than the S&P's.

    Even so, this 47th year brought an end to Buffett's remarkable long-term record of averaging a better-than-20% annual gain in Berkshire's book value per share. For the first time, the average dropped into the teens, hitting 19.8%.

    Much as Buffett would have liked to maintain an average above 20%, he had for years known it would slip away. He has repeatedly warned Berkshire's shareholders that the company's huge capital base--$165 billion at the end of 2011--would inevitably slow gains in per-share book value.

    Per-share book value changes are the customary way that Buffett reports shareholder results because this method incorporates all of Berkshire's capital gains and losses whether these are realized or unrealized. Because Berkshire (BRKA) holds such a giant portfolio of common stocks ($77 billion at yearend) and has accumulated large unrealized gains, changes in their level can be important to results.

    Under the more commonly used financial standard of earnings (which reflect no unrealized gains and only certain unrealized losses), Berkshire reported Class A per-share results for 2011 of $6,215 versus $7,928 in 2010.

    An important reason for the decline in earnings (and also for the relatively modest gain in book value per share) is that 2011 was a difficult year for Berkshire's core insurance business. Catastrophe losses were high--$2.6 billion in total--and pricing was not generous.

    Overall, Berkshire's insurance businesses had an underwriting profit in 2011 of only $248 million against just over $2 billion in 2010. The company's reinsurance business, which writes very large policies and suffered $800 million of losses from earthquakes in New Zealand and Japan, was in the red, showing losses of $714 million.

    In his chairman's letter, Buffett focused not on the level of profits in this one year, but on the fact that 2011 was the ninth consecutive year in which Berkshire's insurance operations produced an underwriting profit. In most other corners of the insurance world, by sharp contrast, underwriting losses are common.

    In Berkshire's nine years of underwriting profits, its "float" -- money that doesn't belong to Berkshire, but that it gets to invest for its own benefit -- has grown from $41 billion to $70 billion. Buffett said in his letter that he does not expect float to grow much beyond that, because the amount is already outsized in relation to Berkshire's premium volume.