While Xbox One sales have certainly picked up with the release of the Xbox One S back in August, Microsoft still refuses to release actual sales numbers.
Therefore, we have to rely on metrics from third parties to see how close the race actually is between the consoles, and that's where SuperData comes in. They've revealed in a new article, that the Xbox One hovers around 26 million units sold.
This is an estimate made by experts, but far from official confirmation though, but if true, there's still a long way off from the 55 million PS4 consoles.