This data – on every UK Top 10 hit, taken at 10-year intervals – comes from a study on alcohol references in music, published in Psychology Of Music last month. The study is less interesting to me than this one fascinating table, which puts a bit of concrete data around trends in pop over the last 30 years. They even significance tested it! I’ll add my analysis under the cut.

TOTAL SONGS: This confirms that there was a “pop bubble” in the early 00s – simply put, far more records got into the Top 10 in 2001 than in any of the other years surveyed.

WEEKS IN CHART: Here’s where things get interesting. This data shows that the glut of records did have an impact on how long a Top 10 hit stuck around – only 22% of them managed 10 or more weeks in the chart. BUT this change wasn’t as dramatic as it might have felt – the figure in 1981 was only 29%.

Long hits were never the norm – until now, when the mean number of weeks a Top 10 hit lasts has risen dramatically, presumably thanks to a shift from physical to digital purchasing (there are no longer limits on the number of units available to buy, so the “tail” of a hit can be a lot longer).

What does that mean? It means that the idea that the charts in the 80s reflected ‘real’ hits, and the charts in the 90s and after didn’t, may not be backed up by the data. Top 10 hits behaved roughly the same way throughout the physical music era, sticking around for (on average) between 7 and 9 weeks then falling away.

The download era, on the other hand, seems much more effective in locating hits which have longer-term support. One counter-intuitive conclusion is that the charts may actually be BETTER than ever at identifying songs people want to buy for longer. (Of course, the way records are promoted plays a huge part, and we don’t have data on the average sales of a top 10 hit).

% AT NUMBER ONE: Here’s where you do see the effects of pop marketing in the 90s – the 2001 figures show an uptick in the proportion of Top 10 hits reaching No.1, which probably does represent the efficiency of the record industry in managing release and radio schedules. This is an art they’ve only got better at by 2011, when almost 1 in 4 Top 10 hits gets its turn at the top.

Taken with the previous data, this suggests that what changed wasn’t the overall demand for a song (within the context of the Top 40), but simply that marketers got good at frontloading demand – a high proportion of sales then a tail-off, rather than a rise and fall. But the overall lifespan of a hit changed a lot less than it seemed (until downloading).

GENRE: The weakest part of the data, simply because it’s so subjective which genre any hit is – a “pop” song in 2011 sounds very different from a “pop” song in 1981. Broadly, we see a peak and fall in dance music, a decline and collapse of rock, and a rise of “R&B” which includes hip-hop. Which fits with what anyone might observe.

ORIGIN: This is interesting – evidence for the globalisation of the US record industry in the 80s. As I wrote in Zero Books’ Michael Jackson book, Thriller was both evidence for this and an accelerant of it, setting new expectations for the levels a global audience might reach. The proportion of British records in the UK Top 10 falls sharply between 81 and 91 and continues to decline after that, with American records moving in.

In the paper the authors suggest this is because of a shift in trends towards R&B and hip-hop, but that doesn’t really account for the 81 to 91 shift, when hip-hop was important in the UK but not yet the default language of pop. I’d suggest instead that the globalisation of the biz during the 80s made it easier to export a distinctively American genre AND to maintain the (financially very helpful) perception that US hip-hop was more authentic and higher-quality.

ARTIST: Another fascinating, and very little discussed, shift. 10s pop, by this reckoning, is defined by a collapse in interest in the group/band as a format, with solo acts prospering and collaborations between them taking up the slack. This trend should delight accountants and managers at least. It’ll be very interesting to see if this is a blip, which the data happened to catch, or something longer-term.

The individuation of pop via reality TV, and in fact via social media, would be good rationalisations for what’s going on here, as well as technological trends moving away from the idea of bands and band-based music.

GENDER: And finally, something I have noticed, though haven’t quite got round to writing about yet (if only I’d seen this in a few Popular entries time…) – a steady decline in male presence in the Top 10 and a rise in female presence – “mixed” presumably means groups and collaborations with both men and women billed.

This doesn’t tell the whole story – backroom staff from producers to executives remain very strongly male, I’d guess. But it’s interesting – if not surprising – that the steady rise to prominence of women acts over this period coincides with the rise of a desire to dismiss the charts as in decline, less relevant, ‘unrepresentative’, etc.