The late quarter launch of the iPhone 5 and lower prices on older models prevented total shipment volumes from slipping to 3Q11 levels.

ENGADGET: IDC: Android claims 75 percent of smartphone shipments in Q3, 136 million handsets sold

Apple's iPad once again led the market, and the firm's shipment total of 22.9 million units was exactly in line with IDC's forecast for the period.

ENGADGET: IDC: iPad loses a little marketshare, still dominates global tablet sales in Q4 2012

With a 24% decline in HDD ASPs, s, a 50% unit shipment growth and a 13.5% increase in total revenues over five years it is obvious that HDDs have been experiencing declining profit margins over this period.

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