But the return on equity is not, especially in the insurance & reinsurance sectors. This is an industry trend and if you look at the low valuations of insurance properties (many are trading below book value) you begin to understand why the market has trimmed BURP's valuation.
Because BRK has a large portfolio of equities it's reported earnings and thus return on equity are less than a true picture of earnings power (only portfolio dividends are included in earnings). A better proxy for return on equity is growth in book value which was 10.2% annually over the last 10 years, much better than the S&P.
Comparing BRK to other insurers P/B is also a bit misleading since most of BRK's book value is in it's operating companies many of which were acquired years ago. Plus BRK is a much better than average insurer based on historical combined ratio.
BRK is a powerhouse that trades essentially for a P/E less than 12 (less than 1.2 times book and book growth <earnings proxy> of 10%/yr). Mr Market, like the previous poster, gets confused and apathetic. But if you are patient, BRK may be the best risk/reward in the market today.