R-12 demand question

[christopher_bender@fmc.com (CHRISTOPHER BENDER)]

     Hi All,
     
     I have a question/theory that I have been thinking about, but i have 
     no evidence to support or dispute it.
     
     On first thought, since virgin R-12 is no longer being manufactured 
     in the US, one might think its price will continue to increase as 
     supplies are consumed.
     
     But the theory I was thinking of is, demand may fall faster than 
     supply.  How?  This could happen in two ways:  Cars using R-12 are 
     taken out of service, or cars are fitted with R-134a conversion kits. 
      The cars that need R-12 service are getting older, as a group, each 
     year, and as such, they may be taken out of service for a number of 
     reasons (accident damage exceeding value of car, major mechanical 
     failure).  Secondly, consumers may be pushed to buy R-134a kits by 
     shady repair shops who use scare tactics like telling them that R-12 
     is illegal, or it won't be available in less than a year, or 
     something like that.
     
     Does anyone have any ideas on where data about the number of cars and 
     ages of cars in service in the USA is, and is anyone monitoring the 
     rate of sales of R-134a conversions?  Using such data, could anyone 
     make an educated guess as to whether my theory might be correct?
     
     Mandatory Audi content:  I ask this question as I am contemplating 
     changing my Audi (86 4000Q, 100k miles) over to R-134a, or, should I 
     feel comfortable in keeping it as R-12, assuming that the entire car 
     has at most another ten years of life, before it is no longer 
     serviceable?
     
     
     Chris