The music industry should be dreaming of a white Christmas

By THE DATA TEAM

FOR many countries across the world December 1st marks the beginning of the Christmas season. Decorations are retrieved from attics; trees are felled; frantic gift-buying begins; and festive music rings out. Christmas pop songs are a genre in their own right, and a money-spinner at that. The 13 most popular Christmas songs on Spotify, a music-streaming service, have amassed 1bn plays between them. The most popular of them, “All I Want for Christmas Is You”, written in 15 minutes and recorded by Mariah Carey in 1994, accounts for 210m of those plays. It has earned over $60m in royalties since its release.

Despite its ubiquity during December, the appeal of festive music varies significantly by geography. Spotify provided The Economist with data for Christmas listening across 35 countries, and for every American state, on a day-by-day basis for the two months leading up to Christmas Day 2016. The data demonstrate that music lovers in Sweden and Norway listen to festive tunes most frequently. One in every six songs they streamed on Spotify during December last year received this classification (the list includes some 1,500 Christmas songs performed in English and local languages). By contrast, during the same period in Brazil—a country with a comparable proportion of Christians—just one song in 150 was Christmas-themed. Listening habits in American states also vary, though to a smaller degree: in New Hampshire Christmas songs accounted for one in nine streams, whereas in Nevada, the state where such tunes are least common, it was one in 20.

What might cause these differences between Spotify users’ appetites for festive-themed music? After comparing daily streaming data against a number of factors, it appears that daylight hours, weather and religiosity are big drivers of behaviour. After accounting for the amount of time remaining before Christmas and the day of the week—the songs are most popular at the weekend—it turns out that Christmas listening is most prevalent in countries that have the fewest daylight hours and the wettest weather. Across our sample of 25 countries in the northern hemisphere, every additional hour of darkness is correlated with a three-percentage-point increase in the amount of Christmas listening on Spotify. The weather affects festive spirits too. Rainy days increase Christmas listening by 0.5 percentage points over dry days.

In America, festive listening appears similarly fickle across states. An additional hour of darkness increases listening by 1.5 percentage points, and colder weather brings a slight increase in listening. A fall in a state’s average daily temperature of 10 degrees Celsius is associated with a 0.1 percentage-point rise in Christmas song-streaming. The biggest bump is reserved for snowfall, which causes a two-percentage-point increase in streaming. And states that are more pious—measured by the percentage of people in the state that report attending weekly worship—have a greater propensity to listen to Christmas-themed music.

That the weather and daylight hours drive consumer behaviour may not surprise many. Walmart, America’s biggest retailer, has long known that sales of strawberry-flavoured Pop-Tarts, a snack food, rise sevenfold ahead of a hurricane. And all told, our simple model explains about 50% of the variation of Christmas music between countries and between states. What might be driving the other half remains as elusive as Santa Claus himself. (Spotify reports that the demographic make-up of its users is broadly similar between countries and states.) And we do not know whether these changes in Christmas listening cause people to consume less music as a whole, or simply to switch to festive fare from other kinds of music.

The implications of our findings for the music industry might be brushed aside. After all, the nights draw longer and the weather becomes increasingly inclement in the northern hemisphere with remarkable regularity, year after year. But woe betide a mild December: our back-of-the-envelope calculations show that 20% fewer snow days across America during November and December would reduce the royalties from Ms Carey’s infectious hit by some $10,000.

Listen along with Spotify's Christmas Classics playlist