PLANSPONSOR, a leading national retirement industry magazine, has recognized Principal Financial Group Inc. as one of the top 20 leaders in the retirement plan industry of the past 20 years.  Principal, which provides services to more than 43,000 retirement plans covering nearly 4.3 million participants, was recognized for its "dedication to ensuring that small retirement plans get large plan service."  PLANSPONSOR presented the award on March 27 at the 2013 Awards for Excellence ceremony in New York City.