Winds from Hurricane Ike will cost insurance companies at least $553.1 million to cover property damage and other losses in Ohio, making it the state's most expensive natural disaster in more than three decades, a trade group said Tuesday.

When other expenses are tallied, including government cleanup costs, last month's windstorm may top financial losses reported after a 1974 tornado devastated the western Ohio town of Xenia, the Ohio Insurance Institute said.

About 2.6 million Ohio utility customers lost power after remnants of Ike swept through the state, knocking down power lines and trees and damaging homes and businesses. At least seven of the 72 deaths blamed on Hurricane Ike were in Ohio.

Insurers said the hardest-hit area was southern Ohio, especially near Dayton, Cincinnati and Columbus.

The Ohio Insurance Institute surveyed two-dozen insurers that handled a record of nearly 132,000 claims from Ohio home, vehicle and business owners because of the Sept. 14 windstorm. The survey represents about two-thirds of the Ohio auto and home insurance market and one-third of the commercial market.