Amazon has announced impressive sales of its Echo devices over the Christmas period. Jeff Wilke, CEO Worldwide Consumer for Amazon, said that the Echo Dot was the best-selling and "most gifted" item of the year, leading to worldwide stock issues for the product. Wilke added that even with increased production, the company “still had trouble keeping [the Echo and Echo Dot] in stock". High sales show an increased interest in 'virtual assistant' devices, whilst increasing long-tail searches show an increasing comfort in voice recognition technology. A survey from Strategy Analytics estimates that 1.8 million digital voice-activated devices have been sold in the US alone this year, with penetration expected to rise from 2% this year to close to 11% in 2020.