U.S. life carrier mortality has been remarkably low.

Only 3 life insurance companies and 3 health carriers failed in 2005, and the companies that did fail were small, according to a report by analysts at Standard & Poor’s, New York.

The number of life insurer and health carrier failures was the same as in 2004, and the only failed life insurer rated by S&P had just $12 million in assets.

Despite the effects of Hurricane Katrina, only 10 property-casualty insurers failed in 2005, down from 13 in 2004, and none of the p-c carriers domiciled in Louisiana or Mississippi was placed under regulatory supervision last year.

Although the total number of failures dropped only 19%, the asset value of the top 5 2005 failures amounted to just $112 million, down from $5.3 billion in 2004.

“Such favorable trends, however, are not sustainable over the long term,” S&P analysts warn in the report.

Elsewhere in the report, the analysts predict that the quest for scale will encourage life insurers to continue to consolidate during the coming year.