Seasonal adjustment is an important step of the official statistics business architecture and harmonisation of practices has proved to be key element of quality of the output. In this spirit, since the 90s, Eurostat has been playing a role in the promotion, development and maintenance of a free software solution (Demetra) for seasonal adjustment in line with established best practices. In 2011 a new software, called Demetra+, was released. It consists in a .NET encapsulation of the two leading…