For what it's worth, I think most of us mix our color on the run as we need them. I did so yesterday, mixing Tamiya red and black acrylics to get the right dark red shade I needed for an MSD ignition unit.
But I don't keep any particular mixes handy.
My work is by eye. If it looks right, it is. So I think the whole concept of color is in the eye of the beholder.