Wasn't able to figure out when this was published but on page 3 is a table showing the affects of color on sales prices. There's some other interesting (to me) stuff on colors in general.
http://www.uaex.edu/Other_Areas/publications/PDF/FSA-3067.pdf
dun
http://www.uaex.edu/Other_Areas/publications/PDF/FSA-3067.pdf
dun