The addition of downloads to the UK charts meant that singles could reach number one with no physical copy being released. The first single to achieve this was Gnarls Barkley's "Crazy" in early 2006. Since 2014, audio streaming has been included in the calculation of chart position, so it is now possible for a single to reach number one without selling any copies (if it were only available on streaming services). In the week ending 24 September 2015, "What Do You Mean?" by Justin Bieber became the first number one with over half of its chart sales made up of streaming points, with sales of 30,000 and 36,000 points from 3.6 million streams.