Swain's passive tooltip should track how much permanent health it grants

Every other champ with a similar stacking mechanic tracks the stacked stat in its tooltip (when it's visible in an existing stat, such as Sion's health) or as a buff (when it isn't, such as Nasus's Q strength). Why doesn't Swain's new health-stacking passive, which grants 5 max health each time he gets a Soul Fragment, have this? It should have this.