http://www.camaros.org/exterior.shtml#ColorPercentages
I am not sure you will be successful with figuring out an accurate way to calculate values on colors.. Why was Frost Green & Fathom Green 8 & 10% of production but now (especially Frost) is not a desirable color today to most people? But like you said Black was 2.0% and is very popular today.. Because color preferences come and go. Orange, silver, red and yellow have always been popular colors for the majority. I guess I am the odd man out because I like the unique and none conventional colors because it makes it different.
Heres a couple charts for comparison sake.
It's a change in taste. If you were around back then, you probably remember all the green cars running around. Green was hugely popular in the late 60's and early 70's, not just chevy, but all makes and models. It's the original color I still see the most on data plates when customer cars roll in here, even though they've been repainted in the past with black or red.
For me, I never lost the flavor for greens. I prefer either really light greens (like Frost) or the really dark greens like Fathom or Verdero. The greens in between don't do much for me. I also still love golds, which was another very often seen color in the late 60's and early 70's.
I've noticed a trend in the last 5-6 years as well. More and more people are going back to these original colors on there cars no matter how rare (or not) or undesirable the color might be today. More and more are coming back. In my opinion I think it's refreshing to see. I absolutely enjoyed painting these T-birds pictured here back into their original colors, coral sand and willow green. These colors grow on you after a while.
But to answer the question, I would only consider paying more for a color that I like, not because it's rare. I much rather enjoy seeing the greens and golds and soft yellows like butternut, so I would actually pay more for those, I'm tired of reds and blacks. No offense to anyone.
Pfff, nevermind, photobucket isn't working correctly. I really dislike these computers.