TSC Ratings provides exclusive stock, ETF and mutual fund ratings and commentary based on award-winning, proprietary tools. Its "safety first" approach to investing aims to reduce risk while seeking solid outperformance on a total return basis.Citigroup ( C) and Principal Financial Group ( PFG) units are among the country's 22 strongest life insurers, suggesting they may have an edge in attracting customers concerned about the stability of financial companies. Topping the list of life insurers with A-plus ratings that earned annual life premiums of $100 million or more and representing at least 10% of their business were American Family Life, State Farm Life, State Farm Life & Accident and Country Life. Primerica Life Insurance, a Citigroup division, and Principal Life Insurance, part of Principal Financial Group, maintained their A-minus ratings, according to a quarterly review of financial strength ratings by TheStreet.com Ratings. Among the A-plus firms, American Family Life is headed by Jack Salzwedel, president; State Farm Life and State Farm Life & Accident are run by Edward Rust Jr., president; and Country Life is overseen by Phillip Nelson, president. Companies that entered the bear market with the most capital, relative to the riskiness of their assets, have weathered the storm the best, the study shows. Life insurers need to hold large sums of securities, and many have posted massive losses during the stock market crash, damaging earnings and capital. Still, the rout has ebbed. Life insurance stocks have, on average, tripled since a March 9 low after plummeting 85% in the previous five months. Even though 12 of the 22 strongest companies posted declines in capital last year, ranging from 1% to 38%, they all passed TheStreet.com Ratings' stress test. The stress test is designed to determine whether a company has enough capital to withstand a prolonged, severe recession. Three insurers, led by John Hancock Life Insurance of New York, a subsidiary of Manulife Financial Group ( MFC), hold more than twice the amount needed during a severe recession, TheStreet.com Ratings found in its review. The strongest companies aren't necessarily the largest life insurers in the industry. Those with the best marks show a consistent history of strong profitability, steady capital growth, good asset quality and excellent overall stability.