Value Display (the field on the right) displays the value, or position in space, of a highlighted key. This is an editable field. You can enter a new number or expression to change the value of selected keys.
Key Entry toolbar with Value Display field outlined
To move an object in space using Value Display:
The Value Display shows the X, Y, or Z Position key spatial value.
The new value takes effect. If the time slider is at or near the same frame as the key, the change is visible in the viewports.
Example: To add 10 to the values of specific keys:
Each key's value is incremented by 10. Simply entering 10 would give each key a value of 10.