Start with 100 cents: one semitone
Two neighboring piano keys are usually one semitone apart, or 100 cents. A 20-cent deviation is not one note away; it is one fifth of a semitone.
Read the sign before the size
A positive value means sharp; a negative value means flat. First identify the direction, then the size, so you know whether to nudge up or ease down.
Read a short curve, not one instant
Sung pitch naturally moves. A better check is whether the curve stays around the target for 3 to 5 seconds, not whether one frame happens to show 0.