The rarest M&M color is brown. It was introduced in 1995 and was the last color to be added to the M&M's lineup. It is also the least popular color among consumers.
based on 712 M&M's, he decided the color breakdown was now 19.5% green, 18.7% orange, 18.7 percent blue, 15.1 percent red, 14.5 percent yellow, and 13.5 percent brown, which would make Steve's beloved brown M&Ms the odd ones out.
