I haven't looked recently, but I don't remember there being any DD found for 2017D or is this not a DD?
Die Deterioration Doubling. On the right side of your coin the doubling is on the right and and left on left side. It has to do with Metal Flow and Die Wear in those directions when all the doubling is on the edge side of the designs.
Look at the difference between the 2014 and the 2017 see how the 2014 adds to the devices, They are thicker and at the same height. On the 2017 the secondary devices are shallow and seem to take away from the details.
