Tag Expression for Placement By Minute?

I guess tag expression coding is something I don’t follow. When I use the above tags, it advances the image okay, but not at the absolute value, it just advances by the amount specified from its starting point wherever it is. So if an image is originally placed where Y = 180 (in the middle) then the code above moves the image by the listed values, but by moving it based on its original position, not by an absolute position. I can work with this, but ideally I would want to specify the image’s actual XY coordinates at any point in the tag expression.