Mr. Dunn, who had a 28-year career with Best Buy, had been cutting staff jobs and shifting to smaller store formats as a response to competition from internet retailers such as Amazon. Best Buy has also been streamlining its creative messages and increasing spending. It has purchased time during the Super Bowl the past two years.
The company ranks as the 56th-largest advertiser, with $666.5 million in U.S. ad spending, including measured and unmeasured media, according to Ad Age 's DataCenter. It works with CP&B, Razorfish, Starcom and CHI/Wunderman.
"The Best Buy team and I will be extremely focused on successfully managing this period of transition," Mr. Mikan said in a statement. "I want to assure our employees, customers and other key stakeholders that we will work together to achieve our company's growth and profitability goals."