Private U.S. property and casualty insurers' net income after taxes in the first quarter was essentially flat year over year at $17.9 billion, according to Verisk Analytics Inc. and the American Property Casualty Insurance Association.

That figure was well above the $11.9 billion average quarterly income for the past 10 years and is the highest quarterly income since the industry recorded $18.2 billion in the first quarter of 2015.

P&C insurers' surplus was $771.9 billion as of March 31, down from $847.8 billion as of Dec. 31, 2019. The pandemic-induced equity market drop in March drove the largest-ever quarterly decline in surplus for P&C insurers for the month, the report stated.

Aside from that historic drop in surplus, results for the first quarter were not visibly affected by COVID-19, the report added. The stock market recovered most of its March losses by the end of June.

The industry's combined ratio improved year over year to 94.9% from 95.6%. Excluding mortgage and financial guaranty insurers, commercial lines insurers' combined ratio deteriorated 1.3 percentage points to 97.7%. Personal lines insurers' combined ratio improved 2.7 percentage points to 92.2%, while balanced insurers' combined ratio improved 1.1 percentage points to 95.8%.

Net written premiums increased 6.2% to $164.4 billion from $154.7 billion for the first quarter of 2019. Net written premium growth for insurers writing mostly personal lines slowed to 3.0% from 4.5% a year earlier. Excluding mortgage and financial guaranty insurers, net written premium for insurers writing predominantly commercial lines increased 12.1% after falling 9.3% in the first quarter of 2019, while premium growth for insurers writing more balanced books of business accelerated to 3.2% in the first quarter from 2.9% a year ago.

Net underwriting gains increased to $6.3 billion from $5.2 billion a year earlier.

Net investment income, primarily dividends from stocks and interest on bonds, was essentially flat year over year at $13.2 billion.

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