North American property & casualty insurers were hit hard bycatastrophe losses in the first 9 months of 2017, leading to adeterioration in operating results, a new Fitch Ratings special report explains.

Fitch Ratings compiled 9 month GAAP financial results for 52P&C reinsurers that are publicly traded or report GAAPconsolidated results.

Related: 2017 to be one of the costliest catastrophe lossyears ever, Fitch says

The 9 month GAAP financial results for this group show operatingreturn on equity (ROAE) declined to 4.3% compared to 7.1% in thefirst nine months of 2016. The Fitch report says only 7 out of the52 P&C insurers reported an operating ROAE above 10% throughthe first three quarters of this year.

Driven by Hurricanes Harvey, Irma and Maria, reportedcatastrophe losses nearly tripled from this time last year to $27.9billion, compared to $9.7 billion in 2016. 2017 could end up beinga record year for insured catastrophe losses, as various industryestimates expect losses to reach $70-100 billion.

"The reinsurance and Florida specialist segments were especiallyhit hard by catastrophe losses, which represented nearly 25% andover 16% of earned premium through the first nine months of thisyear, respectively," said Director Chris Grimes of Fitch Ratings.Fitch believes that 2017 may see a record for insured catastrophelosses for the U.S. P/C market. 

Related: Hurricanes Harvey and Irma recreational boat lossesestimated at $655 million

Strong investment results offset the weaker underwritingearnings, the report explains. The aggregate group (excludingBerkshire Hathaway Inc.) reported realized gains of $2.1 billion inthe first 9 months of 2017, up from a $400 million realized loss in2016.

Boosting operating results across all sectors, net investmentincome increased to $36.5 billion, compared to $34.6 billion in theprevious year.

Fitch maintains a Stable Rating Outlook for each of the sectorscovered in this report (U.S. commercial, U.S. personal, andglobal reinsurance). Broad-based rating changesare unlikely in the next 12-24 months. Personal and commerciallines have stable sector outlooks, while the reinsurance sector'soutlook is negative, as intense market competition and sluggishcedent demand have resulted in a soft reinsurance capacity.

Fitch's "North American Property & Casualty Insurers NineMonth 2017 Results" special report is available at www.fitchratings.com.

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