Berkshire Hathaway’s first-quarter net insurance underwriting earnings grew 4.1% to  $US480 million ($614.1 million), driven by its reinsurance unit.

Overall net profit in the three months to March 31 increased to $US5.16 billion ($6.6 billion) from $US4.71 billion ($6 billion) in the corresponding period last year.

Pre-tax underwriting gains from Berkshire Hathaway Reinsurance Group improved to $US459 million ($587 million) from $US183 million ($234 million), mainly on the strength of its property and casualty business.

However, premium earned fell to $US1.45 billion ($1.85 billion) from $US2.02 billion ($2.58 billion).

“There were no losses from significant catastrophe events [this year or last year],” the company says.

Motor vehicle insurer Geico’s pre-tax underwriting profit fell to $US160 million ($205 million) from $US353 million ($452 million), as increasing claims frequencies and severities took their toll.

Higher losses and loss adjustment expenses also affected the motor insurer, which earned premium of $US5.39 billion ($6.9 billion), up from $US4.88 billion ($6.26 billion).

General Re made a pre-tax loss of $US47 million ($60 million) as earned premium fell to $US1.5 billion ($1.92 billion) from $US1.56 billion ($2 billion).

Net investment income grew to $US875 million ($1.12 billion) from $US720 million ($921.6 million), lifted by higher dividend payouts from equity securities.