Originally Posted by Speed Racer
Nope, the base for pretty much all the coat colors is red, so of course chestnut/sorrel is the most common.
This isn't true. Red is the base for the red based colours - chestnut (or sorrel, depending on your location), palomino, cremello, red dun, dunalino, etc.
Black is the base colour for so many more colours. Black, bay, brown, buckskin, smoky black, brownskin, perlino, smoky cream, smoky brown (or a double dilute brown horse, whatever you feel comfortable calling it), grullo, bay dun, brown dun, perlino dun, smoky cream dun, smoky brown dun, and so on.
Definitely far more colours that are black based than there are colours that are red based.