chibcicylist said:
A good indicator would probably be jagged spikes on sales charts near the launch dates and a gradual evening out the farther you go from the launch period. Then use averages or something. Some math nerd can figure it out.
I'm a bit hesitant to go that route. From sales charts, it looks as though PS3 stopped being supply-constrained around the first couple of weeks of this year, which is probably about right. However, generally manufacturers stockpile hardware before launch for shipment in the first few weeks (those jagged spikes you're talking about), and when that stockpile runs out, they'll ship as many as production allows, which should be a steady rate. From my point of view it's difficult to tell the difference between a post-launch period that's showing steady sales as a result of freely-available hardware and steady demand, and a post-launch period where the steady sales are the result of a supply-constrained market buying every unit of a console that's being shipped at a steady rate.
That said, it'd probably be a good starting point, so I might make some guesses from sales charts and then ask the Japanese gaffers here if they seem about right.
Edit:- Here's what I've come up with from charts on JoshuaJSlone's site, all based on Famitsu numbers:
PS2 - Week 7 - 10th April 2000 - ~1,300,000
GBA - Week 8 - 7th May 2001 - ~1,700,000
GC - Week 3 - 24th Sept 2001 - ~200,000
XBox - Week 3 - 4th March 2002 - ~170,000
DS - Week 7 - 10th Jan 2005 - ~1,450,000
PSP - Week 9 - 31st Jan 2005 - ~750,000
XB360 - Week 3 - 19th Dec 2005 - ~85,000
PS3 - Week 11 - 15th Jan 2007 - ~600,000
Wii - Still supply constrained - 2,000,000+
I could be off by up to a month on some of them (the point at which sales "steady off" is rather hard to determine), so anecdotal verification/refutation would be very much appreciated. I'm also a bit weary that some of them include holiday sales, which could skew the numbers.