Berkshire Hathaway’s insurance operations have provided a $US66 billion ($65 billion) float to fund the group’s other investments, according to Chairman Warren Buffett.

He told shareholders in the 2010 annual report that the investment conglomerate’s underwriting operations made a net profit of $US1.3 billion ($1.28 billion) for 2010, up 37%, while investment income from its insurance operations fell 9% to $US3.8 billion ($3.74 billion.)

The insurance operations earned $US30 billion ($29.5 billion) in gross written premium (GWP).

Of its four major insurance arms, auto insurer Geico increased its underwriting profit by 72% to $US1.1 billion ($1 billion), while Gen Re’s underwriting profit fell 5% to $US452 million ($445 million).

Berkshire Hathaway Reinsurance’s profit fell by 30%, to $US176 million ($173 million) while other smaller insurers in the group more than doubled their contribution to $US268 million ($264 million).

Mr Buffett says Berkshire Hathaway’s insurance activities have remained strong and are “not negatively impacted in any significant way” by the US recession.

General Re’s GWP declined by 5% to $US5.6 billion ($5.5 billion), reflecting lower volume because of price competition in most property and casualty lines.

Berkshire Hathaway’s reinsurance group reported catastrophe loses of about $US308 million ($303 million) from the Chilean and NZ earthquakes, Gulf of Mexico oil rig explosion and Australian floods.