...and Pet Shop Boys came out on top

Music experts have conducted research on Christmas No. 1s to determine what makes a sure-fire festive hit.

Analysing every Christmas No. 1 from the past 50 years, record label Ostereo found that Pet Shop Boys’ version of Elvis’ ‘Always On My Mind’ is closest to being the perfect Yuletide chart-topper.

According to the research, a track is more likely to win the Christmas chart battle if it is three minutes and 57 seconds in length, in the key of G major, has a speed of 114 bpm, and is performed by a solo artist aged 27.

It was also found that nearly half of the No. 1’s analysed were covers, almost all were not about Christmas, and many were ballads.

1987’s ‘Always On My Mind’ is said to have the ideal key and length – while being a cover also worked in its favour. Despite carrying some of the formula’s characteristics, ‘Always On My Mind’ is performed by a duo – who had an average age of 31.5 – and is slightly too fast at 125 bpm.

“I think we’re a long way from an algorithmically-generated Christmas number one,” said Howard Murphy, founder of Ostereo, in a press release. “But certain characteristics do make a song more likely to resonate with audiences at Christmas.

“You can’t turn an average song into a hit at any time of year – never mind Christmas – so adding sleigh bells to a Christmas song won’t make a difference if the song isn’t already great.”

He added: “For example, without the church bells at the end, East 17’s Stay Another Day is still a great song, but it’s not a Christmas song.”

However, Murphy stated that “clever instrumentation can enhance the festive feel” of a track, and therefore its success over the Christmas period.

Meanwhile, the bookies’ odds for 2018’s Christmas No. 1 were revealed earlier this week.

At present, Ariana Grande is set to remain in the top spot with her latest single ‘Thank U, Next‘. However, the pop star faces tough competition – with Elton John, Miley Cyrus and Mark Ronson, Ava Max, and Clean Bandit also in the running.

Last year, Ed Sheeran bagged the Christmas No. 1 with a reworked version of his single ‘Perfect’.