 While less clear, there is also a tendency for early tracking to reduce mean performance.Tracking was once popular in English-speaking countries, but is less used now; tracking systems formed the basis of the Tripartite System in England and Wales until the 1970s, and in Northern Ireland until 2009.In the UK the term "Tracking" refers to recording data as to individual pupils progress, the term "Streaming" commonly translates to the meaning of Tracking in the sense of this article.