At first, Panda Express restaurants were found solely in food courts in major shopping malls. During the late 1980s and early 1990s, the Cherngs began experimenting with supermarket-based branches, through a deal with Vons, and then stand-alone restaurant locations. In 1997, the company opened its first stand-alone, drive-through restaurant, in Hesperia, California. Today less than 2% of its restaurants are in malls. Because Peggy had worked for several years as a software designer and engineer for defense contractors like McDonnell Douglas, Panda Express computerized its operations early on. Peggy also brought a systems analysis perspective to the business and worked through the logistics and standardization issues necessary to scale up the concept. In 2005, Panda Express began to open units in food courts on college campus, some of which participate in the residential student meal plans. In 2008, the Cherngs were the recipients of the City of Angels Award, given by the LAX Coastal Area Chamber of Commerce, for their contributions to the greater Los Angeles area. As of 2007, the company's highest revenue location, bringing in over US$4 million annually, was located at the Ala Moana Center food court in Honolulu, Hawaii. On November 23, 2009, it was announced that Panda Express had selected Trusonic to provide Asian themed background music to its store locations. On the ABC News TV program Nightline, April 18, 2011, there was a feature segment on Panda Express and its success. The segment described how Andrew Cherng encourages his workers and management to go through self-help programs emphasizing Landmark Education. In 2011, a suit was filed by the Equal Employment Opportunity Commission against Panda Express because it was reportedly treating its Hispanic employees differently than Asian employees. In June 2013, it was announced that the restaurant chain will pay $150,000 to settle another EEOC action on behalf of at least three female teenagers who were allegedly sexually harassed between 2007 and 2009 by one male kitchen supervisor in Kauai, Hawaii. In addition to the fines, Panda Express revised its policies and was required to provide anti-discrimination and sexual harassment training for employees. Later that year, Panda Express opened its first location in the western Pacific by opening a location in the American territory of Guam. The first location in the state of Alaska was later opened in December 2015. As of 2017, the Panda Restaurant Group had annual sales of over $3 billion and