In terms of album sales, this has not been a good year for so-called "established" artists. The latest offering from a blue chip celeb to feel the chilly blast of consumer indifference is the new album by - let's be brief - Prince. Even allowing for the fact that it costs at least Pounds 20 and lasts for three hours, his triple CD, Emancipation, has got off to an ominously slow start. In its first week in the stores - a period during which Prince-sized names and their expectant fans normally generate plenty of business on a wave of pre-release hype - Emancipation barely scraped into the top 20.
It will be scant consolation to the number crunchers at the little chap's new label that this disappointing showing is, currently, pretty much par for the course. For reasons that are not yet entirely clear, the market for music by rock stars of a certain age has softened dramatically over the past 12 months. The trend established in the late 1980s - when CD-buying became the norm, and passing 30 looked, for the first time since the war, like a wise commercial move for many successful pop stars - has suddenly been reversed.
The first casualty of the new ageist bias was Wild Mood Swings by the Cure, an album that arrived in the spring, was quite favourably reviewed and then promptly sank without trace. Unremarked at the time, this came as quite a shock, not least to the group's leader, Robert Smith, who had for years been regarded as the Peter Pan of the indie community. Cure fans, previously renowned for their loyalty and devotion to black leather, big hair and eyeliner, seemed, after 20 years, to have jumped ship. Every other album the band released before Wild Mood Swings has outsold its predecessor; this one put them back to a level they last visited in the early 1980s.
And so it has gone on. Other surprise underachievers this year have included Sting's Mercury Falling, New Adventures in Hi-Fi by REM, and Phil Collins, whose abrupt fall from grace with Dance into the Light really set alarm bells ringing. Only six years ago Collins shifted 2.7m copies of...But Seriously in Britain alone. His new album, scheduled to benefit from the record-buying surge in the run-up to Christmas, has skulked out of the top 30 barely a month after release.
Looked at on a case-by-case basis, each of these comparative failures can be explained away somehow or other. It is pointed out that Prince's album sales have been slowly dwindling for several years. His last, Chaos and Disorder, is whispered to have sold only 30,000 copies in the UK. REM, on the other hand, are said to be actively discouraging custom: after three commercial blockbusters, and a series of health scares during their last tour, the band are reportedly fed up with the pressures of success, and are trying to scare away a section of their mainstream support.
The Cure, who seem in their sulky way to have rather enjoyed getting bigger and more famous, are thought simply to have been away too long. In the four years since their last album, Wish, grunge and Britpop have possibly rendered their introspective angsty style obsolete. As for Collins, well, his female fanbase allegedly disapprove of him walking out on his wife and kids and relocating in Switzerland with a younger woman. Then again, maybe his album wasn't that good - the only reason anybody has so far come up with to explain why things have gone so quiet recently for Sting. Though, of course, if his next single were to be a hit, the picture would change dramatically.
The more of this special pleading you hear, the less convincing any of it sounds, particularly when seen in the larger context. At the same time as the over-35s have lost their sway with the album-buying public here, younger acts have been doing spectacularly well. Oasis, as ever, provide the barometer for the greening of the market. Having racked up more than 5m album sales in the UK over the past two years, the band has opened, or rather kicked down, the door for a raft of young British guitar bands. Names that were virtually unknown a year ago, such as Cast, Ocean Colour Scene and Kula Shaker, have all performed startlingly well.
But Britpop is itself only a symptom of what looks and sounds like a broader generational takeover. Alanis Morissette, the 23-year-old Canadian whose album Jagged Little Pill has already passed the 2m mark here, sings about decaying relationships with far greater authority now than Phil Collins. The complexity of musical references in The Score by Fugees - 800,000 copies sold in the UK - offers more pleasure currently than Sting. Even the teenpop sensations of the moment, Spice Girls, address their audience with a confidence unseen in a pure pop band since the heyday of Wham!
Compare the album sales of all of these newcomers to those of the more "established" set - there is no comparison - and it is hard to avoid the conclusion that, for the first time since Live Aid, the mainstream pop agenda has been wrested back into the hands of the young or at least the under-30s. Disregard the success of the middle-aged vocal duo Robson and Jerome, whose versions of Silent Night and A Nightingale Sang on Berkeley Square place them firmly in a pre-Beatles time warp, and pop feels more sprightly and, well, more pop than it has for well over a decade.
Cheerful as this may sound for the long-term health of the record industry, the immediate commercial benefits are less certain. It is probably too early to say whether the unexpectedly poor performance of Collins, REM et al has had any direct effect on the Christmas market, but, at a time when most other retail sectors are booming, album sales are reportedly moving forward at a more dignified pace. How to get those old Prince and Cure fans to invest in youth is a problem new Labour and its pop-friendly leader ought perhaps to start addressing now.