Question: What was the ranking, on 2016 Fortune 500 list,  of the insurance company which has Seymour G. Sternberg as its chairman ? 

Context articles: Clorox
Unum
Sonic Automotive
Accident Fund
MainStay Investments
Humana
Lithia Motors
The Guardian Life Insurance Company of America
New York Life Insurance Company
Seymour G. Sternberg

The Clorox Company (formerly Clorox Chemical Co.), based in Oakland, California, is an American worldwide manufacturer and marketer of consumer and professional products with approximately 8,000 employees worldwide as of June 30, 2016.
 The company’s fiscal year 2016 net sales were $5.8 billion, which ranked the company at #455 on "Fortune’s" 2016 Fortune 500 list.
Unum Group is a Chattanooga, Tennessee-based Fortune 500 insurance company formerly known as UnumProvident.
 Unum Group was created by the 1999 merger of Unum Corporation and The Provident Companies and comprises three distinct businesses Unum US, Unum UK, and Colonial Life.
 Its underwriting insurers include The Paul Revere Life Insurance Company and Provident Life and Accident Insurance Company.
 Unum is the top disability insurer in both the United States and United Kingdom and also offers other insurance products including accident, critical illness and life insurance.
Sonic Automotive, Inc. () is a Fortune 500 company based in Charlotte, North Carolina, and is the fifth largest automotive retailer in the United States.
 The company’s founder and Executive Chairman O. Bruton Smith is also the Executive Chairman and a director of Speedway Motorsports (NYSE: TRK).
 Sonic ranked 297th on the 2016 Fortune 500 list.
 The company also is a member of the Russell 2000 index.
Accident Fund Insurance Company of America is an American workers' compensation insurance company headquartered in Lansing, Michigan.
 The company is a member of AF Group, a premier provider of innovative insurance solutions.
 Insurance policies may be issued by any of the following companies within AF Group: Accident Fund Insurance Company of America, Accident Fund National Insurance Company, Accident Fund General Insurance Company, United Wisconsin Insurance Company, Third Coast Insurance Company or CompWest Insurance Company.
MainStay Investments is a U.S. investment management company based in Jersey City, New Jersey.
 Founded in 1986, MainStay Investment's parent company is New York Life Insurance Company, the largest mutual life-insurance company in the United States, and one of the largest life insurers in the world, ranking #61 on the 2016 Fortune 500 list.
Humana Inc. is a for-profit American health insurance company based in Louisville, Kentucky.
 s of 2014 Humana has had over 13 million customers in the U.S., reported a 2013 revenue of US$41.3 billion, and has had 51,600 employees.
 In 2013, the company ranked 73 on the Fortune 500 list, which made it the highest ranked (by revenues) company based in Kentucky.
 It has been the third largest health insurance in the nation.
Lithia Motors, Inc. is an American nationwide automotive retailer headquartered in Medford, Oregon.
 It is the fourth largest automotive retailer in the United States.
 In 2015, Lithia Motors broke into the Fortune 500 list at #482, making it one of only three Oregon-based companies in the Fortune 500.
 This followed a year that saw the acquisition of the DCH Auto Group, one of the 10 largest dealer groups in the country, with 27 dealerships, before being purchased by Lithia Motors.
 In 2016, Lithia climbed to #346 and that same year made the Fortune 500 List of Top Ten Companies with the biggest Jump in rank on the Fortune 500.
 Today, Lithia is ranked #318 on the Fortune 500.
 Lithia employs more than 11,100 people in stores across the nation including Alaska and Hawaii.
 Lithia operates 160 stores in 18 states.
The Guardian Life Insurance Company of America is one of the largest mutual life insurance companies in the United States.
 Based in New York, New York, it has approximately 8,000 employees in the United States and a network of over 3,000 financial representatives in more than 70 agencies nationwide.
 It currently ranks 254th on the Fortune 500 list of largest corporation in the United States.
 In 2015, Guardian achieved the highest earning in its 155-year history with $7.3 billion in capital and $1.5 billion in operating costs.
 Founded in Manhattan in 1860, the company offers a wide range of insurance products and services, including life insurance, disability income insurance, annuities, investments, dental, and vision.
New York Life Insurance Company (NYLIC) is the largest mutual life-insurance company in the United States, and one of the largest life insurers in the world, ranking #61 on the 2016 Fortune 500 list, with about $550 billion in total assets under management, and more than $21 billion in surplus and AVR.
 In 2007, NYLIC achieved the best possible ratings by the four independent rating companies (Standard & Poor's, AM Best, Moody's and Fitch).
 Other New York Life affiliates provide an array of securities products and services, as well as institutional and retail mutual funds.
Seymour "Sy" Sternberg (born June 24, 1943) is Chairman and former CEO of New York Life Insurance Company.
 He retired as CEO on June 30, 2008.
 He also sits on the Board of Directors for the United States Chamber of Commerce, Northeastern University, CIT Group Incorporated, the New York City Leadership Academy, and Express Scripts Holdings.