Since 1969 generations of Brits have held a Sunday afternoon vigil as the new official UK Top 40 was revealed on BBC Radio One.
But one of the nation’s great traditions could soon come to an end as the music industry plans to radically alter how the charts are compiled.
From this summer, the release day for new singles will change from Monday to Friday, which means the official chart is likely to shift too.
So after 46 years of teens and music fans tuning in at 7pm on a Sunday to hear the nation’s new number one, here’s our Top 40 countdown of Top 40 facts.
40 Before the start of the Official Top 40 on Radio One in 1969 there was no offical chart. It was roughly gauged by sales in the US, sales of sheet music and by charts compiled by the New Musical Express and later the publications Record Mirror, Record Retailer and Melody Maker published their charts too.
39 Following the death of Margaret Thatcher in 2013, Ding Dong! The Witch is Dead got to number two in the charts with 52,605 copies sold. Out of a mark of respect BBC Radio One decided NOT to play the 51-second track.
38 In 1984 the BBC banned the playing of Frankie Goes to Hollywood’s saucy track Relax from radio and TV broadcasts - with Radio One’s Top 40 the only one to play it.
37 The biggest selling Top 40 single ever was Elton John’s Princess Diana tribute song Candle in the Wind 1997. It sold 4.9 million copies after her tragic death in a Paris car crash, aged 37.
36 The first official singles chart was compiled from the sales of just 250 record shops, randomly chosen from a sample of 6,000 stores.
35 In 1993, legendary Top 40 presenter Bruno Brookes accidentally played the full, uncensored version of Killing in the Name by Rage Against the Machine, which contains 17 extreme expletives and the BBC received a string of complaints as a result.
34 The first Top 40 countdown on Radio One was presented by Alan Freeman and was snappily titled Pick of the Pops.
33 Boney M have two of the top ten biggest selling UK singles - Mary’s Boy Child and Rivers of Babylon, both released in 1978. It’s a claim no other artist can make.
32 The longest running presenter of the chart was Mark Goodier, now 53, who did the Sunday night countdown from 1995 to 2002.
31 At 16 weeks, Bryan Adams’ 1991 single Everything I Do (I Do It for You) still holds the title for the most consecutive weeks at the top of the chart. It was the theme tune to hit Kevin Costner movie Robin Hood: Prince of Thieves.
30 The only time the Radio One countdown didn’t happen was during the coverage of Princess Diana’s funeral in 1997.
29 Madonna is the most successful female artist in the UK charts with no less than 13 number one singles - the first being 1985’s Into the Groove and the last 2008’s Justin Timberlake duet, 4 Minutes.
28 At its peak some three million people tuned into the Radio One’s Top 40. Figures now hover around 1.3millon
27 In 2004 iTunes sparked the dowloading revolution which means that some 99 per cent of UK single sales now come from downloads. In September, Pharrell Williams’ song Happy became the most-downloaded track of all time in the UK.
26 In 2007, Westlife became the first act to have their first seven singles go to number one in the charts.
25 Single sales have doubled over the past 35 years. In 1979, 89 million singles were sold in the UK, now the figure is closer to 180million.
24 In 2006 Crazy by Gnarls Barkely became the first number one single to go straight to number one on the back of downloads alone.
23 In 1977, Wings’ Mull of Kintyre - Paul McCartney’s band after The Beatles - became the first UK single to sell more than 2million copies.
22 The first one hit wonder in the official UK Top 40 was Zager and Evans’ In the Year 2525 which got to number one in August 1969. They never hit the big time again.
21 Some of the more interesting one hit wonders have included 1971’s Grandad by Clive Dunn, of Dad’s Army fame, Nizlopi’s JCB song in 2005 and the St Winifred’s School choir’s There’s No one Quite Like Grandma in 1980.
20 Some apparent shoo-ins for the number one spot were foiled by more unexpected tracks. In 1981 Ultravox’s epic Vienna was beaten by Joe Dolce’s Shaddap you Face and in 1987 The Pogues Fairytale of New York was beaten by Pet Shop Boys' cover of Always on my Mind.
19 EastEnders and Neighbours top the charts when it comes to soap actors recording hit singles. Walford Square gave us tunes by Anita Dobson, Nick Berry, Michelle Gayle and Sean Maguire while Ramsay Street gave us Kylie Minogue, Jason Donovan and Craig “Hey Mona” McLachlan.
18 In the year 2000 there were no less than 43 singles reaching number one - that’s almost a different song every week. In 1992 there were just 12 number ones - that’s one a month.
17 Jameela Jamil became the first solo female presenter of the chart show in 2013 and handed over the reins to Clara Amfo earlier this year.
16 The first hit by a non-human was Sugar Sugar in 1969 by The Archies, who were an animated TV series based on comic book characters.
15 Ahead of Remembrance Sunday, in 2010 the Royal British Legion’s Two Minutes Silence entered the UK Top 40 at number 19.
14 Kylie Minogue missed out on getting a number one with her song Hand on Your Heart in May 1989 because chart regulations meant that the sales of cassette singles were not included at the time. The rules were soon changed because of this and as a result the single reached the top spot.
13 Unchained Melody holds the offical Top 40 record for being recorded by three different artists, who all hit number one. They are The Righteous Brothers twice in 1965 and 1990, Robson & Jerome in 1995 and Gareth Gates in 2002. It was also recorded several times before the official chart began, including by Jimmy Young in 1955.
12 The first song to reach one million streams in a week was Daft Punk’s Get Lucky featuring Pharrell Williams in 2013.
11 In 2007, actress Billie Piper found her 1999 single Honey To The Bee back in the charts again after a campaign by then Radio One DJ Chris Moyles to test the new chart rules, which meant all downloads counted towards the chart - regardless of when they were released. Billie’s song reappeared at number 17 - eight years after it was originally released.
10 At nine minutes and 38 seconds, All Around The World by Oasis is the longest single to ever top the UK chart. It was released in January 1998 and was 18 seconds longer than the album version.
9 The best-selling record in pop history not to have topped the charts was Wham’s 1984 No.2 hit Last Christmas with sales of 1.45 million. It was beaten by Band Aid’s Do They Know It’s Christmas.
8 The first posthumous number one was Voodoo Chile by Jimi Hendrix which topped the charts on November 21, 1970 - just two months after his death.
7 Dire Straits’ 1985 hit Brothers in Arms was the world’s first CD single but CD singles weren’t counted as part of the UK Singles Chart until 1987. The first number one which was available as a CD single was in May, 1987, Whitney Houston’s I Wanna Dance with Somebody.
6 Frank Sinatra’s My Way still holds the record for the most amount of weeks spent in the UK chart. Since the start of the Official Top 40 in 1969 it’s popped up for a total of 124 weeks at different times. In second place is Snow Patrol’s 2006 classic Chasing Cars which has spent 111 weeks in the chart in total and in third position is Kings of Leon’s 2008 hit Sex on Fire with 90 weeks total.
5 Presenting the Top 40 has proved embarrassing for a number of Radio One presenters. In 2010 Reggie Yates once lost his concentration and swore live on air while in 2012 Greg James once read out a chart that was four weeks out of date.
4 The first single which hit the top of the charts, but couldn’t be played, was Serge Gainsbourg and Jane Birkin Je t’aime... moi non plus. The saucy French track was banned by the BBC.
3 The biggest selling single by a US artist is You’re the One that I Want by John Travolta and Olivia Newton John which sold over 2 million copies in 1978.
2 The Super Furry Animals 1996 hit “The Man Don’t Give A...” contained 49 expletives - a record for a Top 40 single.
1 The longest title of a UK Top 40 hit was Rod Stewart’s Rod Stewart And The Faces’ 1974 hit You Can Make Me Dance, Sing Or Anything (Even Take The Dog For A Walk, Mend A Fuse, Fold Away The Ironing Board, Or Any Other Domestic Shortcomings) with 115 letters.
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