How the Official Charts are compiled

From phoning a small panel of retailers in 1952 to today's highly sophisticated poll of 6,500-plus retailers nationwide, chart compilation has transformed over the decades.

When the very first charts were compiled by the New Musical Express more than 60 years ago, the process was a simple one – pick up the phone, call a few retailers and note down their sales to create the first sales charts in UK history. Today, six decades later and in a completely new millennium, the process could not be more different.

The Official Charts Company prides itself on providing the entertainment industry with the fastest and most accurate charts in the world. For the past 20 years, Leamington Spa-based Millward Brown has been the industry’s appointed chart compilation contractor – managing the vast databases and product identification processes on behalf of the Official Charts Company.

In the UK, the music sector operates a Friday to Thursday chart week (sales counted from 00:01 Friday - 00:00 Thursday), while the video sector operates a Sunday to Saturday chart week (sales counted from 00:01 Sunday – 00:00 Saturday). So, it is just after midnight on Saturday morning (Monday morning for video) that Millward Brown receives the first feeds of data from the 6,500-plus chart-reporting retailers, who together represent an estimated 99% of the singles market, 98% of the albums market and 90% of the video market.

This daily data-delivery process continues through the week, with music data delivered just after midnight on Sunday, Monday, Tuesday, Wednesday and then Thursday. 

Through the week, all of these sales are matched against databases of products (music and video) held by Millward Brown and verified day by day.

By Friday morning, the final day’s music data is added and, by lunchtime, industry clients are receiving their first glance of the week’s totals. This data is offered with multiple breakdowns of every title’s weekly performance – daily breakdowns, plus by region, format and retailer type (with all retailers categorised as either general/specialist, supermarkets, independents and digital).

The complexity of this rapid process should not be under-estimated – in many other key markets, the charts take several days to be delivered to the business, not just the few chart hours in which the UK charts & data are compiled. The process has become increasingly complex in recent years too, through the addition to the chart survey in 2004 of download sales (which are currently double the sales volumes of single sales in the biggest pre-digital eras) and, in 2014, of streaming.

The Official Charts Company has been collecting streaming information since 2008 (when the Official Subscription Plays Chart was launched) but only in 2014 did streaming finally enter the core Official Charts. The first to take on board audio streams was the Official Singles Chart from the beginning of July 2014 - with 100 audio streams (drawn from services such as Spotify, Deezer, Napster and O2 Tracks, among others) equating to 1 single purchase. In January 2017, this was altered so that 150 streams equaled 1 single purchase.

While the addition of streams represented a hugely significant change in the history of the UK’s charts, it should also be seen as the latest step in the evolution of the UK’s Official Charts.

In the earliest days of the UK’s singles chart, the dominant format was the 10-inch vinyl single. Since those days, the 10-inch has been superceded by multiple different formats – over the years, 7 inch, 12-inch, cassingles, 8-track, Digital Compact Cassette, MiniDisc, Compact Disc, USBs, UMD, DVD, Blu-ray, downloads and streams have all had their day, and have all been tracked in Official Charts.

And as consumers’ tastes continue to evolve, so will the Official Charts.