Namewise

Repeatedly exchanged positions

The order between the two changed at least four times in the same published list.

1200 pairs, drawn from the 2,573 names with a recorded popularity standing (common, familiar, uncommon). Every one comes from a single published list, where both names were measured on the same scale, in the same year, by the same registrar — so each is a fact about that ranking rather than a similarity judgement, and never a claim that one name displaced the other.