I would think by now you would know what a square is. You know, the one we all learned about in in geometry and every quilter knows how to make perfectly. Your individual "Northern Cardinal" blocks are NOT square which made for some fudging to make them a 9 inch square. See picture at the 9 inch lines if you don't believe me. (Top right hand corner). The bottom left corner is where the ruler starts.
In future panels, please check that they are geometrically correct or print a label letting people know that they are not.