I looked at my 6D's menu and yes, there is same kind of numbers, RAW 20M, MRAW 11M, SRAW 5M. There is also amount of pixels. For SRAW 2736x1824. If You do the maths, the result is 5MB. It tells about picture quality which is like You used a 5MB camera, not the size of the file in memory card or hard drive.