LONDON--Direct Line Insurance Group PLC (DLG.LN) said it is on track to achieve full year cost base and combined operation ratio targets after strong results in the first half despite major weather events and competitive markets.

The car insurer said gross written premium fell to 1.84 billion pounds ($3.11 billion) from GBP1.98 million in the first half of 2013, while pretax profit rose to GBP225.1 million from GBP208.8 million.

The company announced an interim dividend per share of 4.4 pence representing growth of 4.8% over 2013.

"Our performance has also allowed us to continue to invest in the future of our business, to enhance our product propositions and improve our customer experience," Chief Executive Paul Geddes said.

"We have rolled out self-install telematics boxes, which will enable us to reward better driving, and we've made it easier to buy our Motor products on smartphones and tablets."

Direct Line said it is on track to achieve total cost base target of GBP1 billion in 2014 and reiterated its aim to achieve a combined operating ratio in the range of 95% to 97% for ongoing operations, assuming a normal level of weather claims.

-Write to Rory Gallivan at rory.gallivan@wsj.com; Twitter: @RoryGallivan

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