Apple Health Lb & Stone

Apple Health will not display Stones and pounds correctly. A stone is made up of 14 pounds, and scale will display you weight as whole stones and then pounds e.g. 13st 12 lb. For some bizarre reason the Apple Health app treats 13.12 stone as 13st and 12% of a stone! This means that after weighing myself I need to then work out the % of a stone that equates to 12 pounds. Who on earth works in % of a stone? Can this be fixed?