Despite lower revenues, Loews (L) surged to a 52-week high after the insurer revealed a much stronger-than-expected 15.6% increase in fourth-quarter profit, helped by gains in its investment portfolio.

The New York-based company posted net income of $466 million, or $1.12 a share, compared with $403 million, or 94 cents a share, in the same quarter last year, trumping average analyst estimates polled by Thomson Reuters of 88 cents.

The improvement was attributed by the company to higher net investment income from limited partnerships, as well as increased favorable prior year development at CNA and improved results from its trading portfolio, partially offset by $22 million in investment losses.

Revenue for the commercial property and casualty insurance company was $3.7 billion, down slightly from $3.8 billion a year ago, missing the Street’s view of $3.89 billion.

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