Natural and man-made catastrophes cost insurers $6.7 billion in 1997, down by around half in inflation-adjusted terms from 1996, according to a study by Swiss Re.

Although no extremely costly disasters occurred last year, insured losses were considerably higher than the average for the years 1970 to 1988 but lower than the record years from 1989 to 1996, the insurer said in the latest issue of its sigma bulletin.Natural catastrophes accounted for $24 billion of the $28.8 billion in total losses recorded in the study. Flooding in eastern Europe caused the highest total loss of $5 billion. Earthquakes in Italy cost $4.5 billion.

Eastern European floods triggered the highest insurance loss of the year at $940 million, followed by $500 million in storm damage in Britain late in the year.

There was no single billion-dollar loss in 1997, it said, snapping a string of at least one such big loss recorded by Swiss Re each year from 1989 to 1996.

The study included events that caused an insurance loss of at least $12.7 million for shipping, $25.4 million for aviation and $31.7 million for other losses. The floor for total losses was $63.5 million.

It recorded 348 events that in all claimed more than 22,000 lives. Two-thirds of the victims died as a result of natural catastrophes. Almost 5,000 were killed in storms, another 5,000 in floods and 3,000 in earthquakes.

Typhoon Linda in Vietnam was the most severe storm, killing more than 3,800 people.