technology obsolescence curves are cool

check out this cool technology obsolescence curve. It shows the gradual rise and fall of sales trends of vinyl records, cassette tapes, and compact discs over a 30 year period. unfortunately, no mp3 data. but, lucky us, someone else contributed apple ipod unit sales into swivel, so i threw that into the mix and ended up with an illustrative comparison.

(for now, please ignore the colors — i’ll change them soon.)

so, a couple few interesting observations.

• the obvious thing — why are there way more cd sales? one possible explanation is that it’s a marketing victory. remember those old BMG and columbia house deals where you could buy 30 CDs at a time for some obscenely low price? another, more interesting, explanation is that the cd players became commodity technology fairly quickly which made it widely available to more people, which means the market who consumes cds increased. i have no data on this, but it seems to make sense — electronics become commodities pretty quickly these days.
• the intersection of the tail of vinyl with the head of cds is approximately near the peak of cassette tapes. i wonder if this is a characteristic of technology obsolescence when it comes to music distribution technology.
• the approximate death of vinyl’s sales coincides neatly with the intersection of the tail of cassettes and the head of cds. same goes for the intersection of vinyl and cassettes — it’s approximately the start for compact discs. curious. again, is this a recurring characteristic?
• unit sales of ipods seem to fit in crisply with what we expect after looking at the previous technologies’ osolescence curves. the sales of ipods start at approximately the same time that sales of compact discs begin to slow. not a surprise, but it’s nice to see that actual disparate data sets confirm the regularity of obsolescence cycles. also note the positioning of the intersections. this is telling.

(matt pointed out that wikipedia has a good chunk of itunes music store data. i need to get this into swivel. thanks matt.)

what do you think? what other technology trends can we track for fun (and profit)? i could look at this graph for hours, but i need to make swivel better for a while.

credit for this goes to the swivel community:

seema created the original graph that caught my attention from from data uploaded by c.a.joyce. the data is sourced the world almanac and the riaa, with additional data on ipod unit sales from adpowers