Kate Bush’s Running Up That Hill has reached number one almost 37 years after first being released.

In doing so, it has broken the record for the biggest gap between being released and topping the chart.

The title for the longest-running sleeper hit in the UK was previously held by Wham!.

George Michael and Andrew Ridgeley’s Last Christmas topped the Official Singles Chart last year, 36 years after being released.

Running Up That Hill is also currently number one in Australia, New Zealand, Sweden and Switzerland, and has achieved a new peak in the US charts at number four.

The eighties classic has been heavily featured in the fourth series of Netflix drama Stranger Things, in which Max Mayfield, played by Sadie Sink, is heard listening to the song on her Walkman.

Bush said she liked the way in which Running Up That Hill was featured “in such a positive light, as a talisman for Max”.

Fans of the song – many of whom weren’t even born when it came out in August 1985 – have given it a new lease of life on TikTok.

The lead single from Bush’s fifth studio album, Hounds of Love, it peaked at number three first time around, before reaching 12th spot in 2012.

The 63-year-old’s surprise chart-topper means she is now the artist with the longest gap between number one singles – she also achieved the feat with her debut, Wuthering Heights, in 1978.

And she has become the oldest female artist ever to score a UK number one, replacing Cher, who was 52 when Believe topped the charts in 1998.

“It’s all so exciting!” Bush, who last performed live in 2014, wrote on her website.

“The track is being responded to in so many positive ways. I’ve never experienced anything quite like this before!

“Thank you so much again to the Duffer Brothers – because of their latest, extraordinary series of Stranger Things, the track is being discovered by a whole new audience.”

She added: “I’m overwhelmed by the scale of affection and support the song is receiving, and it’s all happening really fast, as if it’s being driven along by a kind of elemental force.

“I have to admit I feel really moved by it all. Thank you so very much for making the song a No 1 in such an unexpected way.”

Bush could arguably have topped the charts sooner were it not for record industry streaming rules designed to make sure the UK top 10 isn’t weighed down by older tracks which are played consistently on subscription platforms.

To ensure that is not the case, an “accelerated decline” rule was introduced, whereby a new record earns one “sale” when it is streamed 100 times on a subscription service.

Older songs need to be streamed 200 times before a “sale” is counted.

It meant that although Bush comfortably had the most-streamed song in the UK last week, with 2.5 million plays, Harry Styles was number one because he had a more favourable streams-to-sales ratio.

But record labels can request a “manual reset” in “exceptional circumstances” – which is what EMI did, levelling the playing field.