Dafydd Iwan's iconic song "Yma O Hyd" has taken on a new life after being adopted by Welsh football fans but is missing from the Official Charts Top 100.
That is despite an apparently successful campaign to get the Welsh language song soaring up the charts and competing for the top spot alongside Harry Styles, Ed Sheeran and 80s favourite Kate Bush.
After the Welsh men's football team qualified for their first World Cup since 1958 on Sunday there were unforgettable scenes as the players sang their new unofficial anthem on the pitch with the iconic folk singer.
This was followed by a campaign on social media to get "Yma O Hyd" to the top of the charts to celebrate the occasion, with the track reaching the summit of the iTunes chart by Wednesday afternoon.
Despite this, "Yma O Hyd" doesn't appear on the weekly chart published each Friday by the Official Charts Company.
The Official Charts Company is a music industry trade organisation which compiles the latest sales data on behalf of record labels and other industry bodies, and releases this data each week as the official charts. The Top 40 singles are counted down on BBC Radio1 every Friday afternoon.
James Masterton is a chart expert and music writer. Asked about the omission of "Yma O Hyd" from this week's Official Charts Top 100 Singles he said: "It hasn't had the required sales volume over the past seven days to qualify. Being top of the iTunes chart is a neat visual, but this table is reactive, not cumulative".
Apple are secretive about the methodolgy behind the iTunes chart, Masterton continues, "it's believed it represents a rolling average of purchases on that single platform over the preceding 48 hours.
"In the age of streaming, actual purchases of tracks are at such low volumes that it barely requires more than a few hundred concentrated purchases to send a track soaring".
Despite the huge increase in sales of "Yma O Hyd" on iTunes, only around 1.5 per cent of the singles chart is made up of paid downloads according to Masterton. "Streaming equivalent sales account for almost all music consumptions. Singles purchases are now a tiny legacy rump, made mostly by those still clinging on to old habits.
"The weekly singles market can reach 25 million units. Paid purchases represent a mere 370,000 of these."
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