The UK Singles Chart is a music chart compiled by the Official Charts Company (OCC) that calculates the best-selling singles of the week in the United Kingdom.[2] Since 2005, the chart has been based on the sales of both physical and digital singles, initially on the condition that the single was available in both formats. In 2007, the rules were changed so that legal downloads of all songs, irrespective of whether a physical copy was available, were eligible to chart[3] and since July 2014, streaming has been included.[4]