Some addresses may have no collisions at all.
It is unbelievable, but each address exists approximately 2^96 times in the whole 2^256 bit space. (2^256 - 2^160 = 2^96)
So the chances that an address has no collisions at all are ~ 1 to 2^96, that means nearly zero.
We can be sure, that there are always collisions for an address.