DERIVATIVE DIP: Berkshire Hathaway's second quarter net income declined 9 percent to $3.1 billion. That's down from last year's second quarter net income of $3.4 billion.

SUCCESSFUL SUBSIDIARIES: Many of Berkshire's subsidiaries performed well, especially its insurance units and the BNSF railroad. Berkshire's operating profit, which excludes derivatives and investments, jumped 37 percent to $3.7 billion.

INSURANCE IMPROVEMENT: Berkshire's insurance companies added $619 million underwriting profit this year, compared to a $7 million underwriting loss last year. The biggest difference is that few losses from catastrophes hit Berkshire this year. In the first six months of 2011, Berkshire's insurance companies incurred $1.2 billion in catastrophe losses.