When the CK is released I'll look into this option...I knew how to do it in Oblivion, hopefully they've kept it the same.. In the meantime you can keep your mouse cursor on the white "arrow" on the left side of the slider and just spam left click and enter..if you put it in the right spot it automatically moves the slider to one each time you click then hit enter to accept the trade...just be careful you don't accidentally move the mouse. Hope that helps for now.