In this video as part of The Motley Fool's "Ask a Fool" series, Motley Fool Stock Advisor analyst Brendan Mathews takes a question from a Fool reader, who asks: "Can you explain the combined ratio that you use when you talk about insurance companies? How do the combined ratios of popular insurance companies compare?" In this video, Brendan explains the combined ratio, and he highlights two very good underwriters – Berkshire Hathaway (NYSE: BRK-B) and Markel (MKL 0.98%) -- and two companies that haven't done as well – CNA Financial (CNA 1.12%) and American International Group (AIG +0.00%).
What Is the Combined Ratio?
By Brendan Mathews – Feb 4, 2014 at 7:00AM
Learn how to evaluate insurance companies based on a key performance metric -- the combined ratio
Brendan notes the combined ratio is a key measure of underwriting profits -- it measures whether an insurance company is making money on the policies it writes. So here's the formula for calculating it: the combined ratio equals incurred losses plus expenses divided by earned premiums. A ratio under 100 indicates that the company is underwriting at a profit. A ratio above 100 indicates that the company is underwriting at a loss.  
So, again, a ratio below 100 is good -- that means profits on underwriting, a ratio above 100 is bad -- that indicates loses on underwriting. Thus, when looking at an insurance company, it's great to see a combined ratio below 100. And, don't just look at a single year -- check out the company's multi-year history of combined ratios. 
To put things in perspective, Brendan shares the average results of a four companies.   To learn more, watch the video below, and you can also watch Brendan discuss his Top Insurance Stocks for 2014 and Beyond. 
About the Author
Brendan Mathews (TMFWillSommers), a northern Virginia native, began following the Fool as a teenager as part of his lifelong love of investing. He graduated from the University of Virginia as an Echols Scholar, after which he promptly began a nine-year career in the corporate strategy practice of a big consulting firm. Along the way, he picked up an MBA from UC Berkeley and worked briefly at two California hedge funds. But he never forgot about his passion for finding great investments, and he's thrilled to be back in his hometown, working for the Fool. He enjoys scouring financial statements, pontificating on competitive advantage, and any outdoor activity.
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