Progressive Corp.'s (PGR) fourth-quarter earnings fell 2%, with the auto and home insurer reporting lower premiums as the period had one less week than the prior year period.

Shares were down 1.7% at $19 in recent premarket trading.

Progressive's bottom line in recent quarters has been swayed by investment losses and gains, though its premiums have grown. Industry competition remains heated with companies offering additional services and promotions to boost policyholder rolls. Progressive recently unveiled a program offering motorists discounts based on data about their driving habits gathered by a device that plugs into the onboard diagnostic ports of their cars.

FBR analysts recently noted positive trends for auto insurers, including rising gas prices that tend to reduce mileage, growing sales for new cars that tend to carry more expensive premiums than old ones and price increases by many insurers.

Progressive reported a profit of $299.2 million, or 45 cents a share, down from $305 million, or 46 cents a share, a year earlier. The latest period included $77.9 million in pretax investment gains, while the prior year included $45.8 million. The prior period also included an extra week.

Net premiums written decreased 4% to $3.28 billion. Analysts polled by Thomson Reuters most recently forecast earnings of 36 cents on net premiums written of $3.53 billion.

The combined ratio, or amount of premiums paid as claims, rose to 93.1% from 91.5%. Meanwhile the amount of personal auto and special-lines policies in force increased 8% and 5%, respectively.

Copyright © 2011 Dow Jones Newswires