Best Buy’s (BBY) major structural changes may be necessary, but the company is in for a rocky ride during this transitional period. The big box retailer on Tuesday reported that its second-quarter earnings in 2012 totaled $12 million, or $0.04 per share — roughly 91% lower than the $128 million, or $0.34 per share it reported in the second quarter of 2011. The company said the big reason for its decline in profits was that it paid $91 million in restructuring charges related to store closings. Best Buy’s revenues also declined to $10.5 billion in the quarter, down 3% from the $10.8 billion the company reported in Q2 2011. Needless to say, the company’s performance presents an immediate challenge for new Best Buy CEO Hubert Joly, who was officially appointed to the position on Monday.