The error seems to increase on the left, and diminish on the right — usually when this happens it’s caused by the machine being unlevel / out of tram.
Please check that the table and wasteaboard are level, the Y-axis rails are level and parallel, the X-axis gantry rail is level and square to the Y-axis rails, and the Z-axis is plumb and square.
Please see: Wasteboard Plans with threads