Yes and no. While I haven't been able to see if each piece of equipment was done individually (doubt it), the equipment is scaled so that an optimum piece of equipment is always better than a higher level piece of equipment. For example, if you are rank 5 and have a rank 1, 10, and 15 pieces of equipment, the rank 1 piece of equipment will have the same stats as the other pieces until rank 10. At rank 10, the rank 10 piece will have the stats listed on it and will be better than the rank 15 piece until rank 15.
This was only done with Pugilist weapons, so I'm not actually sure if equipment follows the same guidelines, but I suspect it will.